Encoding information in light polarization is of great importance in facilitating optical data storage(ODS)for information security and data storage capacity escalation.However,despite recent advances in nanophotonic ...Encoding information in light polarization is of great importance in facilitating optical data storage(ODS)for information security and data storage capacity escalation.However,despite recent advances in nanophotonic techniques vastly en-hancing the feasibility of applying polarization channels,the data fidelity in reconstructed bits has been constrained by severe crosstalks occurring between varied polarization angles during data recording and reading process,which gravely hindered the utilization of this technique in practice.In this paper,we demonstrate an ultra-low crosstalk polarization-en-coding multilayer ODS technique for high-fidelity data recording and retrieving by utilizing a nanofibre-based nanocom-posite film involving highly aligned gold nanorods(GNRs).With parallelizing the gold nanorods in the recording medium,the information carrier configuration minimizes miswriting and misreading possibilities for information input and output,respectively,compared with its randomly self-assembled counterparts.The enhanced data accuracy has significantly im-proved the bit recall fidelity that is quantified by a correlation coefficient higher than 0.99.It is anticipated that the demon-strated technique can facilitate the development of multiplexing ODS for a greener future.展开更多
Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthe...Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthesis of perovskite nanostructures have been made towards potential device applications.The engineering of their band structures holds great promise in the rational tuning of the electronic and optical properties of perovskite nanostructures,which is one of the keys to achieving efficient and multifunctional optoelectronic devices.In this article,we summarize recent advances in band structure engineering of perovskite nanostructures.A survey of bandgap engineering of nanostructured perovskites is firstly presented from the aspects of dimensionality tailoring,compositional substitution,phase segregation and transition,as well as strain and pressure stimuli.The strategies of electronic doping are then reviewed,including defect-induced self-doping,inorganic or organic molecules-based chemical doping,and modification by metal ions or nanostructures.Based on the bandgap engineering and electronic doping,discussions on engineering energy band alignments in perovskite nanostructures are provided for building high-performance perovskite p-n junctions and heterostructures.At last,we provide our perspectives in engineering band structures of perovskite nanostructures towards future low-energy optoelectronics technologies.展开更多
Nonscattering optical anapole condition is corresponding to the excitation of radiationless field distributions in open resonators,which offers new degrees of freedom for tailoring light-matter interaction.Conventiona...Nonscattering optical anapole condition is corresponding to the excitation of radiationless field distributions in open resonators,which offers new degrees of freedom for tailoring light-matter interaction.Conventional mechanisms for achieving such a condition relies on sophisticated manipulation of electromagnetic multipolar moments of all orders to guarantee superpositions of suppressed moment strengths at the same wavelength.In contrast,here we report on the excitation of optical radiationless anapole hidden in a resonant state of a Si nanoparticle utilizing a tightly focused radially polarized(RP)beam.The coexistence of magnetic resonant state and anapole condition at the same wavelength further enables the triggering of resonant state by a tightly focused azimuthally polarized(AP)beam whose corresponding electric multipole coefficient could be zero.As a result,high contrast inter-transition between radiationless anapole condition and ideal magnetic resonant scattering can be achieved experimentally in visible spectrum.The proposed mechanism is general which can be realized in different types of nanostructures.Our results showcase that the unique combination of structured light and structured Mie resonances could provide new degrees of freedom for tailoring light-matter interaction,which might shed new light on functional meta-optics.展开更多
Modification of reduced graphene oxide in a controllable manner provides a promising material platform for producinggraphene based devices. Its fusion with direct laser writing methods has enabled cost-effective and s...Modification of reduced graphene oxide in a controllable manner provides a promising material platform for producinggraphene based devices. Its fusion with direct laser writing methods has enabled cost-effective and scalable production for advanced applications based on tailored optical and electronic properties in the conductivity, the fluorescence and the refractive index during the reduction process. This mini-review summarizes the state-of-the-art status of the mechanisms of reduction of graphene oxides by direct laser writing techniques as well as appealing optical diffractive applications including planar lenses, information storage and holographic displays. Owing to its versatility and up-scalability, the laser reduction method holds enormous potentials for graphene based diffractive photonic devices with diverse functionalities.展开更多
Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar cells.In this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconver...Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar cells.In this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate system.The quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) sample.Strong and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping concentrations.The Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing material.Moreover,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.展开更多
Complex demographic processes and natural selection pressures are critical to resolving patterns of the molecular genetic basis of adaptive traits or complex diseases.Recent ancient genome data allow us to trace how k...Complex demographic processes and natural selection pressures are critical to resolving patterns of the molecular genetic basis of adaptive traits or complex diseases.Recent ancient genome data allow us to trace how key traits evolved in different human populations over time,connecting ancient population history with disease susceptibility in western Eurasians.To fill this gap in eastern Eurasians and provide deep insights into the evolutionary history of the populationspecific genetic basis of complex biological traits,we explored the evolutionary basis of adaptive traits in one integrative modern and ancient genomic database,including 225 out of 5583 genomes first reported here.We comprehensively characterized the demographic history and biological adaptation of Han Chinese individuals on the Mongolian Plateau based on the allele frequency spectrum and haplotype-resolved fragments.We found strong genetic homogeneity among geographically different Han populations from Inner Mongolia(IMH).We reconstructed their admixture models and demographic events,revealing that IMH had a close genetic relationship with ancient millet farmers and obtained additional gene flow from Altaic-speaking populations.The enrichment of selected candidate genes suggested that essential metabolism-related genes promoted the rapid adaptation of eastern Eurasians to ancient environmental shifts and dietary changes during agricultural innovations.Evolutionary trajectory reconstruction of metabolism-related genes of methylenetetrahydrofolate reductase(MTHFR)and fatty acid desaturase 1(FADS1)suggested that ancient dietary shifts during the Neolithic transition period promoted the differentiated metabolic rate of folate and fatty acid.We revealed the polygenicity of biological adaptation traits and the pleiotropy of adaptive genes,indicating that complex recent polygenic adaptations,genetic interactions,and genotype–phenotype correlations have contributed to the genetic architecture of complex traits in eastern Eurasians.展开更多
Tibeto-Burman(TB)people have endeavored to adapt to the hypoxic,cold,and high-UV high-altitude environments in the Tibetan Plateau and complex disease exposures in lowland rainforests since the late Paleolithic period...Tibeto-Burman(TB)people have endeavored to adapt to the hypoxic,cold,and high-UV high-altitude environments in the Tibetan Plateau and complex disease exposures in lowland rainforests since the late Paleolithic period.However,the full landscape of genetic history and biological adaptation of geographically diverse TB-speaking people,as well as their interaction mechanism,remain unknown.Here,we generate a whole-genome meta-database of 500 individuals from 39 TB-speaking populations and present a comprehensive landscape of genetic diversity,admixture history,and differentiated adaptative features of geographically different TB-speaking people.We identify genetic differentiation related to geography and language among TB-speaking people,consistent with their differentiated admixture process with incoming or indigenous ancestral source populations.A robust genetic connection between the Tibetan-Yi corridor and the ancient Yellow River people supports their Northern China origin hypothesis.We finally report substructure-related differentiated biological adaptative signatures between highland Tibetans and Loloish speakers.Adaptative signatures associated with the physical pigmentation(EDAR and SLC24A5)and metabolism(ALDH9A1)are identified in Loloish people,which differed from the high-altitude adaptative genetic architecture in Tibetan.TB-related genomic resources provide new insights into the genetic basis of biological adaptation and better reference for the anthropologically informed sampling design in biomedical and genomic cohort research.展开更多
Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve ...Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve miniaturization,high resolution,and low cost of polarization imaging systems.Here,we proposed freeform metasurface polarizers derived by adjoint-based inverse design of a full-Jones matrix with gradient-descent optimization.We designed multiple freeform polarizers with different filtered states of polarization(SOPs),including circular polarizers,elliptical polarizers,and linear polarizers that could cover the full Poincarésphere.Note that near-unitary polarization dichroism and the ultrahigh polarization extinction ratio(ER)reaching 50 d B were achieved for optimized circular polarizers.The multiple freeform polarizers with filtered polarization state locating at four vertices of an inscribed regular tetrahedron of the Poincarésphere are designed to form a full-Stokes parameters micropolarizer array.Our work provides a novel approach,we believe,for the design of meta-polarizers that may have potential applications in polarization imaging,polarization detection,and communication.展开更多
The possibility to achieve unprecedented multiplexing of light-matter interaction in nanoscale is of virtue importance from both fundamental science and practical application points of view. Cylindrical vector beams(C...The possibility to achieve unprecedented multiplexing of light-matter interaction in nanoscale is of virtue importance from both fundamental science and practical application points of view. Cylindrical vector beams(CVBs) manifested as polarization vortices represent a robust and emerging degree of freedom for information multiplexing with increased capacities. Here, we propose and demonstrate massivelyencoded optical data storage(ODS) by harnessing spatially variant electric fields mediated by segmented CVBs. By tight focusing polychromatic segmented CVBs to plasmonic nanoparticle aggregates, recordhigh multiplexing channels of ODS through different combinations of polarization states and wavelengths have been experimentally demonstrated with a low error rate. Our result not only casts new perceptions for tailoring light-matter interactions utilizing structured light but also enables a new prospective for ultra-high capacity optical memory with minimalist system complexity by combining CVB’s compatibility with fiber optics.展开更多
Lithium niobate has received interest in nonlinear frequency conversion due to its wide transparency window,from ultraviolet to mid-infrared spectral regions,and large second-order nonlinear susceptibility.However,its...Lithium niobate has received interest in nonlinear frequency conversion due to its wide transparency window,from ultraviolet to mid-infrared spectral regions,and large second-order nonlinear susceptibility.However,its nanostructure is generally difficult to etch,resulting in low-Q resonance and lossy nanostructures for second harmonic generation.By applying the concept of bound states in the continuum,we performed theoretical and experimental investigations on high-Q resonant etchless thin-film lithium niobate with Si O_(2) nanostructures on top for highly efficient second harmonic generation.In the fabricated nanostructured devices,a resonance with a Q factor of 980 leads to the strong enhancement of second harmonic generation by over 1500 times compared with that in unpatterned lithium niobate thin film.Although the pump slightly deviates from central resonance,an absolute conversion efficiency of 6.87×10^(-7) can be achieved with the fundamental pump peak intensity of 44.65 MW/cm^(2),thus contributing to the normalized conversion efficiency of 1.54×10^(-5)cm^(2)/GW.Our work establishes an etchless lithium niobate device for various applications,such as integrated nonlinear nanophotonics,terahertz frequency generation,and quantum information processing.展开更多
Heavily doped colloidal plasmonic nanocrystals have attracted great attention because of their lower and adjustable free carrier densities and tunable localized surface plasmonic resonance bands in the spectral range ...Heavily doped colloidal plasmonic nanocrystals have attracted great attention because of their lower and adjustable free carrier densities and tunable localized surface plasmonic resonance bands in the spectral range from near-infra to mid-infra wavelengths.With its plasmon-enhanced optical nonlinearity,this new family of plasmonic materials shows a huge potential for nonlinear optical applications,such as ultrafast switching,nonlinear sensing,and pulse laser generation.Cu3-xP nanocrystals were previously shown to have a strong saturable absorption at the plasmonic resonance,which enabled high-energy Q-switched fiber lasers with 6.1μs pulse duration.This work demonstrates that both high-quality mode-locked and Q-switched pulses at 1560 nm can be generated by evanescently incorporating two-dimensional(2D)Cu3-xP nanocrystals onto a D-shaped optical fiber as an effective saturable absorber.The 3 dB bandwidth of the mode-locking optical spectrum is as broad as 7.3 nm,and the corresponding pulse duration can reach 423 fs.The repetition rate of the Q-switching pulses is higher than 80 kHz.Moreover,the largest pulse energy is more than 120μJ.Note that laser characteristics are highly stable and repeatable based on the results of over 20 devices.This work may trigger further investigations on heavily doped plasmonic 2D nanocrystals as a next-generation,inexpensive,and solution-processed element for fascinating photonics and optoelectronics applications.展开更多
To explore the pharmacogenomic markers that affect the platinum-based chemotherapy response in non-small-cell lung carcinoma(NSCLC),we performed a two-cohort of genome-wide association studies(GWAS),including 34 for W...To explore the pharmacogenomic markers that affect the platinum-based chemotherapy response in non-small-cell lung carcinoma(NSCLC),we performed a two-cohort of genome-wide association studies(GWAS),including 34 for WES-based and 433 for microarray-based analyses,as well as two independent validation cohorts.After integrating the results of two studies,the genetic variations related to the platinum-based chemotherapy response were further determined by fine-mapping in 838 samples,and their potential functional impact were investigated by eQTL analysis and in vitro cell experiments.We found that a total of 68 variations were significant at P<1×10^(-3)in cohort 1 discovery stage,of which 3 SNPs were verified in 262 independent samples.A total of541 SNPs were significant at P<1×10^(-4)in cohort 2 discovery stage,of which 8 SNPs were verified in 347 independent samples.Comparing the validated SNPs in two GWAS,ADCY1 gene was verified in both independent studies.The results of fine-mapping showed that the G allele carriers of ADCY1rs2280496 and C allele carriers of rs189178649 were more likely to be resistant to platinum-based chemotherapy.In conclusion,our study found that rs2280496 and rs189178649 in ADCY1 gene were associated the sensitivity of platinum-based chemotherapy in NSCLC patients.展开更多
The resonant optical excitation of dielectric nanostructures offers unique opportunities for developing remarkable nanophotonic devices.Light that is structured by tailoring the vectorial characteristics of the light ...The resonant optical excitation of dielectric nanostructures offers unique opportunities for developing remarkable nanophotonic devices.Light that is structured by tailoring the vectorial characteristics of the light beam provides an additional degree of freedom in achieving flexible control of multipolar resonances at the nanoscale.Here,we investigate the nonlinear scattering of subwavelength silicon(Si)nanostructures with radially and azimuthally polarized cylindrical vector beams to show a strong dependence of the photothermal nonlinearity on the polarization state of the applied light.The resonant magnetic dipole,selectively excited by an azimuthally polarized beam,enables enhanced photothermal nonlinearity,thereby inducing large scattering saturation.In contrast,radially polarized beam illumination shows no observable nonlinearity owing to off-resonance excitation.Numerical analysis reveals a difference of more than 2 orders of magnitude in photothermal nonlinearity under two types of polarization excitations.Nonlinear scattering and the unique doughnut-shaped focal spot generated by the azimuthally polarized beam are demonstrated as enabling far-field high-resolution localization of nanostructured Si with an accuracy approaching 50 nm.Our study extends the horizons of active Si photonics and holds great potential for label-free superresolution imaging of Si nanostructures.展开更多
Background: Weight gain during chemotherapy in patients with breast cancer contributes to their poor prognosis. However, a growing number of studies have found that metabolic disorders seem to play a more important ro...Background: Weight gain during chemotherapy in patients with breast cancer contributes to their poor prognosis. However, a growing number of studies have found that metabolic disorders seem to play a more important role in breast cancer prognosis than weight gain. This study aimed to explore the prognostic effects of body mass index (BMI), weight gain, and metabolic disorders on the overall survival (OS) and prognosis of patients with breast cancer who underwent chemotherapy.Methods: Data from the inpatient medical records of patients with breast cancer who underwent chemotherapy at the Beijing Cancer Hospital Breast Cancer Center from January to December 2010 were retrospectively collected, and the patients were followed up until August 2020.Results: A total of 438 patients with stages I to III breast cancer met the inclusion and exclusion criteria. Forty-nine (11.19%) patients died, while 82 (18.72%) patients had tumor recurrence and metastasis at the last follow-up (August 2020). From the time of diagnosis until after chemotherapy, no significant differences were observed in the body weight (t=4.694,P<0.001), BMI categories (χ^(2)=19.215,P=0.001), and incidence of metabolic disorders (χ^(2)=24.841,P<0.001);the BMI categories and weight change had no effect on the OS. Both univariate (χ^(2)=6.771,P=0.009) and multivariate survival analyses (hazard ratio=2.775, 95% confidence interval [CI]: 1.326-5.807,P=0.007) showed that low high-density lipoprotein cholesterol (HDL-C) levels at diagnosis had a negative impact on the OS. The multivariate logistic regression analysis showed that the HDL-C level at diagnosis (odds ratio [OR]=2.200, 95% CI: 0.996-4.859,P=0.051) and metabolic disorders after chemotherapy (OR=1.514, 95% CI: 1.047-2.189,P=0.028) are risk factors for poor prognosis in patients with breast cancer.Conclusions: Chemotherapy led to weight gain and aggravated the metabolic disorders in patients with breast cancer. Low HDL-C levels at diagnosis and metabolic disorders after chemotherapy may have negative effects on the OS and prognosis of patients with breast cancer.展开更多
Lanthanide-doped upconversion nanoparticles emerged recently as an attractive material platform underpinning a broad range of innovative applications such as optical cryptography,luminescent probes,and lasing.However,...Lanthanide-doped upconversion nanoparticles emerged recently as an attractive material platform underpinning a broad range of innovative applications such as optical cryptography,luminescent probes,and lasing.However,the intricate 4f-associated electronic transition in upconversion nanoparticles leads only to a weak photoluminescence intensity and unpolarized emission,hindering many applications that demand ultrabright and polarized light sources.Here,we present an effective strategy for achieving ultrabright and dual-band polarized upconversion photoluminescence.We employ resonant dielectric metasurfaces supporting high-quality resonant modes at dual upconversion bands enabling two-order-of-magnitude amplification of upconversion emissions.We demonstrate that dual-band resonances can be selectively switched on polarization,endowing cross-polarization controlled upconversion luminescence with ultra-high degrees of polarization,reaching approximately 0.86 and 0.91 at dual emission wavelengths of 540 and 660 nm,respectively.Our strategy offers an effective approach for enhancing photon upconversion processes paving the way towards efficient low-threshold polarization upconversion lasers.展开更多
Scalar optical hopfions weaved by nested equiphase lines in the shape of a toroidal vortex are theoretically designed and experimentally demonstrated.This category of hopfions manifesting as a spatiotemporally structu...Scalar optical hopfions weaved by nested equiphase lines in the shape of a toroidal vortex are theoretically designed and experimentally demonstrated.This category of hopfions manifesting as a spatiotemporally structured pulse propagating in space-time may enable encoding and transferring optical topological information in an additional(temporal)dimension.展开更多
The advance of nanophotonics has provided a variety of avenues for light–matter interaction at the nanometer scale through the enriched mechanisms for physical and chemical reactions induced by nanometer-confined opt...The advance of nanophotonics has provided a variety of avenues for light–matter interaction at the nanometer scale through the enriched mechanisms for physical and chemical reactions induced by nanometer-confined optical probes in nanocomposite materials.These emerging nanophotonic devices and materials have enabled researchers to develop disruptive methods of tremendously increasing the storage capacity of current optical memory.In this paper,we present a review of the recent advancements in nanophotonics-enabled optical storage techniques.Particularly,we offer our perspective of using them as optical storage arrays for next-generation exabyte data centers.展开更多
The emerging meta-holograms rely on arrays of intractable meta-atoms with various geometries and sizes for customized phase profiles that can precisely modulate the phase of a wavefront at an optimal incident angle fo...The emerging meta-holograms rely on arrays of intractable meta-atoms with various geometries and sizes for customized phase profiles that can precisely modulate the phase of a wavefront at an optimal incident angle for given wavelengths.The stringent and band-limited angle tolerance remains a fundamental obstacle for their practical application,in addition to high fabrication precision demands.Utilizing a different design principle,we determined that facile metagrating holograms based on extraordinary optical diffraction can allow the molding of arbitrary wavefronts with extreme angle tolerances(near-grazing incidence)in the visible–near-infrared regime.By modulating the displacements between uniformly sized meta-atoms rather than the geometrical parameters,the metagratings produce a robust detour phase profile that is irrespective of the wavelength or incident angle.The demonstration of high-fidelity meta-holograms and in-site polarization multiplexing significantly simplifies the metasurface design and lowers the fabrication demand,thereby opening new routes for flat optics with high performances and improved practicality.展开更多
基金financial supports from the National Natural Science Foundation of China(Grant Nos.62174073,61875073,11674130,91750110 and 61522504)the National Key R&D Program of China(Grant No.2018YFB1107200)+3 种基金the Guangdong Provincial Innovation and Entrepren-eurship Project(Grant No.2016ZT06D081)the Natural Science Founda-tion of Guangdong Province,China(Grant Nos.2016A030306016 and 2016TQ03X981)the Pearl River Nova Program of Guangzhou(Grant No.201806010040)the Technology Innovation and Development Plan of Yantai(Grant No.2020XDRH095).
文摘Encoding information in light polarization is of great importance in facilitating optical data storage(ODS)for information security and data storage capacity escalation.However,despite recent advances in nanophotonic techniques vastly en-hancing the feasibility of applying polarization channels,the data fidelity in reconstructed bits has been constrained by severe crosstalks occurring between varied polarization angles during data recording and reading process,which gravely hindered the utilization of this technique in practice.In this paper,we demonstrate an ultra-low crosstalk polarization-en-coding multilayer ODS technique for high-fidelity data recording and retrieving by utilizing a nanofibre-based nanocom-posite film involving highly aligned gold nanorods(GNRs).With parallelizing the gold nanorods in the recording medium,the information carrier configuration minimizes miswriting and misreading possibilities for information input and output,respectively,compared with its randomly self-assembled counterparts.The enhanced data accuracy has significantly im-proved the bit recall fidelity that is quantified by a correlation coefficient higher than 0.99.It is anticipated that the demon-strated technique can facilitate the development of multiplexing ODS for a greener future.
基金support from Australian Research Council (ARC, FT150100450, IH150100006 and CE170100039)support from the MCATM and the FLEET+1 种基金the support from Shenzhen Nanshan District Pilotage Team Program (LHTD20170006)support from Guangzhou Science and Technology Program (Grant No. 201804010322)
文摘Metal halide perovskite nanostructures have emerged as low-dimensional semiconductors of great significance in many fields such as photovoltaics,photonics,and optoelectronics.Extensive efforts on the controlled synthesis of perovskite nanostructures have been made towards potential device applications.The engineering of their band structures holds great promise in the rational tuning of the electronic and optical properties of perovskite nanostructures,which is one of the keys to achieving efficient and multifunctional optoelectronic devices.In this article,we summarize recent advances in band structure engineering of perovskite nanostructures.A survey of bandgap engineering of nanostructured perovskites is firstly presented from the aspects of dimensionality tailoring,compositional substitution,phase segregation and transition,as well as strain and pressure stimuli.The strategies of electronic doping are then reviewed,including defect-induced self-doping,inorganic or organic molecules-based chemical doping,and modification by metal ions or nanostructures.Based on the bandgap engineering and electronic doping,discussions on engineering energy band alignments in perovskite nanostructures are provided for building high-performance perovskite p-n junctions and heterostructures.At last,we provide our perspectives in engineering band structures of perovskite nanostructures towards future low-energy optoelectronics technologies.
基金financial support from the National Key R&D Program of China (YS2018YFB110012)National Natural Science Foundation of China (NSFC) (Grant Nos. 11674130, 91750110, 61522504 and 61975067)+2 种基金Guangdong Provincial Innovation and Entrepreneurship Project (Grant 2016ZT06D081)Natural Science Foundation of Guangdong Province, China (Grant Nos. 2016A030306016, 2016TQ03X981 and 2016A030308010)Pearl River Nova Program of Guangzhou (No. 201806010040)
文摘Nonscattering optical anapole condition is corresponding to the excitation of radiationless field distributions in open resonators,which offers new degrees of freedom for tailoring light-matter interaction.Conventional mechanisms for achieving such a condition relies on sophisticated manipulation of electromagnetic multipolar moments of all orders to guarantee superpositions of suppressed moment strengths at the same wavelength.In contrast,here we report on the excitation of optical radiationless anapole hidden in a resonant state of a Si nanoparticle utilizing a tightly focused radially polarized(RP)beam.The coexistence of magnetic resonant state and anapole condition at the same wavelength further enables the triggering of resonant state by a tightly focused azimuthally polarized(AP)beam whose corresponding electric multipole coefficient could be zero.As a result,high contrast inter-transition between radiationless anapole condition and ideal magnetic resonant scattering can be achieved experimentally in visible spectrum.The proposed mechanism is general which can be realized in different types of nanostructures.Our results showcase that the unique combination of structured light and structured Mie resonances could provide new degrees of freedom for tailoring light-matter interaction,which might shed new light on functional meta-optics.
基金The authors thank National Natural Science Foundation of China （61522504, 61420106014, 61432007, 11604123） and Guangdong Provincial Innovation and Entrepreneurship Project （2016ZT06D081） for funding supports. M Gu acknowledges the supports from the Australian Research Council （ARC） through the Discovery Project （DP140100849） and Laureate Fellowship Scheme （FL100100099）.
文摘Modification of reduced graphene oxide in a controllable manner provides a promising material platform for producinggraphene based devices. Its fusion with direct laser writing methods has enabled cost-effective and scalable production for advanced applications based on tailored optical and electronic properties in the conductivity, the fluorescence and the refractive index during the reduction process. This mini-review summarizes the state-of-the-art status of the mechanisms of reduction of graphene oxides by direct laser writing techniques as well as appealing optical diffractive applications including planar lenses, information storage and holographic displays. Owing to its versatility and up-scalability, the laser reduction method holds enormous potentials for graphene based diffractive photonic devices with diverse functionalities.
基金partially supported by NSFC(National Natural Science Foundation of China,grant No.12274049)Fundamental Research Funds for the Central Universities(grant No.3132023519).
文摘Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar cells.In this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate system.The quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) sample.Strong and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping concentrations.The Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing material.Moreover,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.
基金We thank all the volunteers who participated in this project and the researchers who provided help and support for this project(Prof.Etienne Patin and Prof.Lluis Quintana-Murci from the Human Evolutionary Genetics Unit of the Institute PasteurProf.Mark Stoneking and Prof.Dang Liu from the Max Planck Institute for Evolutionary Anthropology+5 种基金and Prof.Wibhu Kutanan from Khon Kaen University).We are indebted to Grammarly(https://app.grammarly.com/)for its invaluable contribution to the linguistic refinement and readability enhancement of this manuscript.M.W.is supported by the National Natural Science Foundation of China(82202078)G.H.is supported by the Major Project of the National Social Science Foundation of China(23&ZD203)the Open Project of the Key Laboratory of Forensic Genetics of the Ministry of Public Security(2022FGKFKT05)the Center for Archaeological Science of Sichuan University(23SASA01)the 1.3.5 Project for Disciplines of Excellence,West China Hospital,Sichuan University(ZYJC20002)the Sichuan Science and Technology Program.L.H.is supported by the Open Project of Shanghai Key Laboratory of Forensic Medicine(KF202309).
文摘Complex demographic processes and natural selection pressures are critical to resolving patterns of the molecular genetic basis of adaptive traits or complex diseases.Recent ancient genome data allow us to trace how key traits evolved in different human populations over time,connecting ancient population history with disease susceptibility in western Eurasians.To fill this gap in eastern Eurasians and provide deep insights into the evolutionary history of the populationspecific genetic basis of complex biological traits,we explored the evolutionary basis of adaptive traits in one integrative modern and ancient genomic database,including 225 out of 5583 genomes first reported here.We comprehensively characterized the demographic history and biological adaptation of Han Chinese individuals on the Mongolian Plateau based on the allele frequency spectrum and haplotype-resolved fragments.We found strong genetic homogeneity among geographically different Han populations from Inner Mongolia(IMH).We reconstructed their admixture models and demographic events,revealing that IMH had a close genetic relationship with ancient millet farmers and obtained additional gene flow from Altaic-speaking populations.The enrichment of selected candidate genes suggested that essential metabolism-related genes promoted the rapid adaptation of eastern Eurasians to ancient environmental shifts and dietary changes during agricultural innovations.Evolutionary trajectory reconstruction of metabolism-related genes of methylenetetrahydrofolate reductase(MTHFR)and fatty acid desaturase 1(FADS1)suggested that ancient dietary shifts during the Neolithic transition period promoted the differentiated metabolic rate of folate and fatty acid.We revealed the polygenicity of biological adaptation traits and the pleiotropy of adaptive genes,indicating that complex recent polygenic adaptations,genetic interactions,and genotype–phenotype correlations have contributed to the genetic architecture of complex traits in eastern Eurasians.
基金the National Natural Science Foundation of China(82202078)the Center for Archaeological Science of Sichuan University(23SASA01).
文摘Tibeto-Burman(TB)people have endeavored to adapt to the hypoxic,cold,and high-UV high-altitude environments in the Tibetan Plateau and complex disease exposures in lowland rainforests since the late Paleolithic period.However,the full landscape of genetic history and biological adaptation of geographically diverse TB-speaking people,as well as their interaction mechanism,remain unknown.Here,we generate a whole-genome meta-database of 500 individuals from 39 TB-speaking populations and present a comprehensive landscape of genetic diversity,admixture history,and differentiated adaptative features of geographically different TB-speaking people.We identify genetic differentiation related to geography and language among TB-speaking people,consistent with their differentiated admixture process with incoming or indigenous ancestral source populations.A robust genetic connection between the Tibetan-Yi corridor and the ancient Yellow River people supports their Northern China origin hypothesis.We finally report substructure-related differentiated biological adaptative signatures between highland Tibetans and Loloish speakers.Adaptative signatures associated with the physical pigmentation(EDAR and SLC24A5)and metabolism(ALDH9A1)are identified in Loloish people,which differed from the high-altitude adaptative genetic architecture in Tibetan.TB-related genomic resources provide new insights into the genetic basis of biological adaptation and better reference for the anthropologically informed sampling design in biomedical and genomic cohort research.
基金supported by the National Key Research and Development Program of China(Nos.2022YFB3607300 and 2021YFB2802003)the National Natural Science Foundation of China(NSFC)(No.62075084)the Guangdong Basic and Applied Basic Research Foundation(No.2022B1515020004)。
文摘Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve miniaturization,high resolution,and low cost of polarization imaging systems.Here,we proposed freeform metasurface polarizers derived by adjoint-based inverse design of a full-Jones matrix with gradient-descent optimization.We designed multiple freeform polarizers with different filtered states of polarization(SOPs),including circular polarizers,elliptical polarizers,and linear polarizers that could cover the full Poincarésphere.Note that near-unitary polarization dichroism and the ultrahigh polarization extinction ratio(ER)reaching 50 d B were achieved for optimized circular polarizers.The multiple freeform polarizers with filtered polarization state locating at four vertices of an inscribed regular tetrahedron of the Poincarésphere are designed to form a full-Stokes parameters micropolarizer array.Our work provides a novel approach,we believe,for the design of meta-polarizers that may have potential applications in polarization imaging,polarization detection,and communication.
基金the financial support from the National Key R&D Program of China (2018YFB1107200)the National Natural Science Foundation of China (91750110, 11674130, 61605061, 11674110 and 11874020)+2 种基金the Guangdong Provincial Innovation and Entrepreneurship Project (2016ZT06D081)the Natural Science Foundation of Guangdong Province (2016A030306016, 2016TQ03X981 and 2016A030308010)Pearl River S and T Nova Program of Guangzhou (201806010040)。
文摘The possibility to achieve unprecedented multiplexing of light-matter interaction in nanoscale is of virtue importance from both fundamental science and practical application points of view. Cylindrical vector beams(CVBs) manifested as polarization vortices represent a robust and emerging degree of freedom for information multiplexing with increased capacities. Here, we propose and demonstrate massivelyencoded optical data storage(ODS) by harnessing spatially variant electric fields mediated by segmented CVBs. By tight focusing polychromatic segmented CVBs to plasmonic nanoparticle aggregates, recordhigh multiplexing channels of ODS through different combinations of polarization states and wavelengths have been experimentally demonstrated with a low error rate. Our result not only casts new perceptions for tailoring light-matter interactions utilizing structured light but also enables a new prospective for ultra-high capacity optical memory with minimalist system complexity by combining CVB’s compatibility with fiber optics.
基金supported by the National Natural Science Foundation of China (Grant Nos. 61775084, and 62075088)the National Safety Academic Fund (Grant No. U2030103)+2 种基金the Natural Science Foundation of Guangdong Province (Grant Nos. 2020A1515010791, and 2021A0505030036)the Open Fund of Guangdong Provincial Key Laboratory of Information Photonics Technology of Guangdong University of Technology (Grant No. GKPT20-03)the Fundamental Research Funds for the Central Universities (Grant Nos. 21622107, and 21622403)。
文摘Lithium niobate has received interest in nonlinear frequency conversion due to its wide transparency window,from ultraviolet to mid-infrared spectral regions,and large second-order nonlinear susceptibility.However,its nanostructure is generally difficult to etch,resulting in low-Q resonance and lossy nanostructures for second harmonic generation.By applying the concept of bound states in the continuum,we performed theoretical and experimental investigations on high-Q resonant etchless thin-film lithium niobate with Si O_(2) nanostructures on top for highly efficient second harmonic generation.In the fabricated nanostructured devices,a resonance with a Q factor of 980 leads to the strong enhancement of second harmonic generation by over 1500 times compared with that in unpatterned lithium niobate thin film.Although the pump slightly deviates from central resonance,an absolute conversion efficiency of 6.87×10^(-7) can be achieved with the fundamental pump peak intensity of 44.65 MW/cm^(2),thus contributing to the normalized conversion efficiency of 1.54×10^(-5)cm^(2)/GW.Our work establishes an etchless lithium niobate device for various applications,such as integrated nonlinear nanophotonics,terahertz frequency generation,and quantum information processing.
基金the support from the National Key Research&Development Program(No.2016YFA0201902)Shenzhen Nanshan District Pilotage Team Program(No.LHTD20170006)+1 种基金Australian Research Council(ARC,FT 150100450,IH150100006,and CE170100039)the funding support from China Postdoctoral Science Foundation Grant(No.217M622758).
文摘Heavily doped colloidal plasmonic nanocrystals have attracted great attention because of their lower and adjustable free carrier densities and tunable localized surface plasmonic resonance bands in the spectral range from near-infra to mid-infra wavelengths.With its plasmon-enhanced optical nonlinearity,this new family of plasmonic materials shows a huge potential for nonlinear optical applications,such as ultrafast switching,nonlinear sensing,and pulse laser generation.Cu3-xP nanocrystals were previously shown to have a strong saturable absorption at the plasmonic resonance,which enabled high-energy Q-switched fiber lasers with 6.1μs pulse duration.This work demonstrates that both high-quality mode-locked and Q-switched pulses at 1560 nm can be generated by evanescently incorporating two-dimensional(2D)Cu3-xP nanocrystals onto a D-shaped optical fiber as an effective saturable absorber.The 3 dB bandwidth of the mode-locking optical spectrum is as broad as 7.3 nm,and the corresponding pulse duration can reach 423 fs.The repetition rate of the Q-switching pulses is higher than 80 kHz.Moreover,the largest pulse energy is more than 120μJ.Note that laser characteristics are highly stable and repeatable based on the results of over 20 devices.This work may trigger further investigations on heavily doped plasmonic 2D nanocrystals as a next-generation,inexpensive,and solution-processed element for fascinating photonics and optoelectronics applications.
基金supported by the National Key Research and Development Programs(2016YFC1306900 and 2017ZX09304014,China)National Natural Science Foundation of China(81573508,81874327,81773823,81803640 and 82073943,China)+3 种基金Fundamental Research Funds for the Central Universities of Central South University(2018zzts251,China)The StrategyOriented Special Project of Central South University in China(ZLXD2017003)Youth Science Foundation of Xiangya Hospital,Central South University(2017Q02,China)Hunan Cancer Hospital Climb Plan(YF2020011,China)。
文摘To explore the pharmacogenomic markers that affect the platinum-based chemotherapy response in non-small-cell lung carcinoma(NSCLC),we performed a two-cohort of genome-wide association studies(GWAS),including 34 for WES-based and 433 for microarray-based analyses,as well as two independent validation cohorts.After integrating the results of two studies,the genetic variations related to the platinum-based chemotherapy response were further determined by fine-mapping in 838 samples,and their potential functional impact were investigated by eQTL analysis and in vitro cell experiments.We found that a total of 68 variations were significant at P<1×10^(-3)in cohort 1 discovery stage,of which 3 SNPs were verified in 262 independent samples.A total of541 SNPs were significant at P<1×10^(-4)in cohort 2 discovery stage,of which 8 SNPs were verified in 347 independent samples.Comparing the validated SNPs in two GWAS,ADCY1 gene was verified in both independent studies.The results of fine-mapping showed that the G allele carriers of ADCY1rs2280496 and C allele carriers of rs189178649 were more likely to be resistant to platinum-based chemotherapy.In conclusion,our study found that rs2280496 and rs189178649 in ADCY1 gene were associated the sensitivity of platinum-based chemotherapy in NSCLC patients.
基金National Key Research and Development Program of China(2018YFB1107200)National Natural Science Foundation of China(61805107)Guangdong Provincial Innovation and Entrepreneurship Project(2016ZT06D081).
文摘The resonant optical excitation of dielectric nanostructures offers unique opportunities for developing remarkable nanophotonic devices.Light that is structured by tailoring the vectorial characteristics of the light beam provides an additional degree of freedom in achieving flexible control of multipolar resonances at the nanoscale.Here,we investigate the nonlinear scattering of subwavelength silicon(Si)nanostructures with radially and azimuthally polarized cylindrical vector beams to show a strong dependence of the photothermal nonlinearity on the polarization state of the applied light.The resonant magnetic dipole,selectively excited by an azimuthally polarized beam,enables enhanced photothermal nonlinearity,thereby inducing large scattering saturation.In contrast,radially polarized beam illumination shows no observable nonlinearity owing to off-resonance excitation.Numerical analysis reveals a difference of more than 2 orders of magnitude in photothermal nonlinearity under two types of polarization excitations.Nonlinear scattering and the unique doughnut-shaped focal spot generated by the azimuthally polarized beam are demonstrated as enabling far-field high-resolution localization of nanostructured Si with an accuracy approaching 50 nm.Our study extends the horizons of active Si photonics and holds great potential for label-free superresolution imaging of Si nanostructures.
文摘Background: Weight gain during chemotherapy in patients with breast cancer contributes to their poor prognosis. However, a growing number of studies have found that metabolic disorders seem to play a more important role in breast cancer prognosis than weight gain. This study aimed to explore the prognostic effects of body mass index (BMI), weight gain, and metabolic disorders on the overall survival (OS) and prognosis of patients with breast cancer who underwent chemotherapy.Methods: Data from the inpatient medical records of patients with breast cancer who underwent chemotherapy at the Beijing Cancer Hospital Breast Cancer Center from January to December 2010 were retrospectively collected, and the patients were followed up until August 2020.Results: A total of 438 patients with stages I to III breast cancer met the inclusion and exclusion criteria. Forty-nine (11.19%) patients died, while 82 (18.72%) patients had tumor recurrence and metastasis at the last follow-up (August 2020). From the time of diagnosis until after chemotherapy, no significant differences were observed in the body weight (t=4.694,P<0.001), BMI categories (χ^(2)=19.215,P=0.001), and incidence of metabolic disorders (χ^(2)=24.841,P<0.001);the BMI categories and weight change had no effect on the OS. Both univariate (χ^(2)=6.771,P=0.009) and multivariate survival analyses (hazard ratio=2.775, 95% confidence interval [CI]: 1.326-5.807,P=0.007) showed that low high-density lipoprotein cholesterol (HDL-C) levels at diagnosis had a negative impact on the OS. The multivariate logistic regression analysis showed that the HDL-C level at diagnosis (odds ratio [OR]=2.200, 95% CI: 0.996-4.859,P=0.051) and metabolic disorders after chemotherapy (OR=1.514, 95% CI: 1.047-2.189,P=0.028) are risk factors for poor prognosis in patients with breast cancer.Conclusions: Chemotherapy led to weight gain and aggravated the metabolic disorders in patients with breast cancer. Low HDL-C levels at diagnosis and metabolic disorders after chemotherapy may have negative effects on the OS and prognosis of patients with breast cancer.
基金supporting by national Key R&D Program of China(2021YFB2802003,2022YFB3607300)the China Postdoctoral Science Foundation funded project(No.2022M711241)+1 种基金National Natural Science Foundation of China(NSFC)(62075084)the Guangdong Basic and Applied Basic Research Foundation(2022B1515020004).
文摘Lanthanide-doped upconversion nanoparticles emerged recently as an attractive material platform underpinning a broad range of innovative applications such as optical cryptography,luminescent probes,and lasing.However,the intricate 4f-associated electronic transition in upconversion nanoparticles leads only to a weak photoluminescence intensity and unpolarized emission,hindering many applications that demand ultrabright and polarized light sources.Here,we present an effective strategy for achieving ultrabright and dual-band polarized upconversion photoluminescence.We employ resonant dielectric metasurfaces supporting high-quality resonant modes at dual upconversion bands enabling two-order-of-magnitude amplification of upconversion emissions.We demonstrate that dual-band resonances can be selectively switched on polarization,endowing cross-polarization controlled upconversion luminescence with ultra-high degrees of polarization,reaching approximately 0.86 and 0.91 at dual emission wavelengths of 540 and 660 nm,respectively.Our strategy offers an effective approach for enhancing photon upconversion processes paving the way towards efficient low-threshold polarization upconversion lasers.
文摘Scalar optical hopfions weaved by nested equiphase lines in the shape of a toroidal vortex are theoretically designed and experimentally demonstrated.This category of hopfions manifesting as a spatiotemporally structured pulse propagating in space-time may enable encoding and transferring optical topological information in an additional(temporal)dimension.
基金The authors thank the Australian Research Council for its support through the Laureate Fellowship project(FL100100099).
文摘The advance of nanophotonics has provided a variety of avenues for light–matter interaction at the nanometer scale through the enriched mechanisms for physical and chemical reactions induced by nanometer-confined optical probes in nanocomposite materials.These emerging nanophotonic devices and materials have enabled researchers to develop disruptive methods of tremendously increasing the storage capacity of current optical memory.In this paper,we present a review of the recent advancements in nanophotonics-enabled optical storage techniques.Particularly,we offer our perspective of using them as optical storage arrays for next-generation exabyte data centers.
基金supported by the National Key R&D Program of China(YS2018YFB110012)the National Natural Science Foundation of China(NSFC)(Grant 11604217,61522504,61420106014,11774145,11734012,11574218)+3 种基金the Fundamental Research Funds for the Central Universities(Grant 21617410)the Guangdong Provincial Innovation and Entrepreneurship Project(Grant 2016ZT06D081,2017ZT07C071)the Applied Science and Technology Project of the Guangdong Science and Technology Department(2017B090918001)the Natural Science Foundation of the Shenzhen Innovation Committee(JCYJ20170412153113701).
文摘The emerging meta-holograms rely on arrays of intractable meta-atoms with various geometries and sizes for customized phase profiles that can precisely modulate the phase of a wavefront at an optimal incident angle for given wavelengths.The stringent and band-limited angle tolerance remains a fundamental obstacle for their practical application,in addition to high fabrication precision demands.Utilizing a different design principle,we determined that facile metagrating holograms based on extraordinary optical diffraction can allow the molding of arbitrary wavefronts with extreme angle tolerances(near-grazing incidence)in the visible–near-infrared regime.By modulating the displacements between uniformly sized meta-atoms rather than the geometrical parameters,the metagratings produce a robust detour phase profile that is irrespective of the wavelength or incident angle.The demonstration of high-fidelity meta-holograms and in-site polarization multiplexing significantly simplifies the metasurface design and lowers the fabrication demand,thereby opening new routes for flat optics with high performances and improved practicality.
