Flexible aqueous Ni//Zn batteries have attracted much attention as promising candidates for energy storage in the field of flexible electronics.However,the Ni-based cathodes still face the challenges of poor conductiv...Flexible aqueous Ni//Zn batteries have attracted much attention as promising candidates for energy storage in the field of flexible electronics.However,the Ni-based cathodes still face the challenges of poor conductivity,confined charge/mass transfer,and non-flexibility.In this work,we designed a hollow tubular structure consisting of a conductive silver nanowire (Ag NW) wrapped by active Ni Co layered double hydroxide (LDH),for enhancing the electrical conductivity,improving the charge/mass transfer kinetics,and facilitating the ion penetration.By optimizing the contents of Ni,Co and Ag NW,the Ni_(4)Co LDH@Ag_(1.5)NW composite shows a maximum specific capacity of 115.83 m Ah g^(-1)at 0.1 A g^(-1)measured in a two-electrode system.Highlightingly,the flexible aqueous Ni//Zn battery assembled by Ni_(4)Co LDH@Ag_(1.5)NW interwoven with multi-walled carbon nanotube cathode and Zn foil anode realizes a high power density of 160μW cm^(-2)at the energy density of 23.14μWh cm^(-2),which is superior compared with those of oxide/hydroxide based devices and even higher than those of many carbon-based supercapacitors,showing its promising potentials for flexible energy storage applications.展开更多
Nitrogen-vacancy(NV)centers in diamond are progressively favored for room-temperature magnetic field measurement.The signal to noise ratio(SNR)optimization for NV diamond magnetometry generally concentrates on signal ...Nitrogen-vacancy(NV)centers in diamond are progressively favored for room-temperature magnetic field measurement.The signal to noise ratio(SNR)optimization for NV diamond magnetometry generally concentrates on signal amplitude enhancement rather than efficient noise processing.Here,we report a compound filter system combining a wavelet denoising method and an adaptive filter for the realization of an efficient weak magnetic measurement with a high SNR.It allows enhanced magnetic field measurement with an average SNR enhancement of 17.80 dB at 50 nT within 500 mHz to 100 Hz and14.76 dB at 500 mHz within 50 n T to 1100 n T.The introduction of this system in NV diamond magnetometry is aimed to improve signal quality by effectively eliminating the noise and retaining ideal signals.展开更多
Multi-band signal propagation and processing play an important role in quantum communications and quantum computing.In recent years,optical nonreciprocal devices such as an optical isolator and circulator are proposed...Multi-band signal propagation and processing play an important role in quantum communications and quantum computing.In recent years,optical nonreciprocal devices such as an optical isolator and circulator are proposed via various configurations of atoms,metamaterials,nonlinear waveguides,etc.In this work,we investigate all-optical controlled nonreciprocity of multi-band optical signals in thermal atomic systems.Via introducing multiple strong coupling fields,nonreciprocal propagation of the probe field can happen at some separated frequency bands,which results from combination of the electromagnetically induced transparency(EIT) effect and atomic thermal motion.In the proposed configuration,the frequency shift resulting from atomic thermal motion takes converse effect on the probe field in the two opposite directions.In this way,the probe field can propagate almost transparently within some frequency bands of EIT windows in the opposite direction of the coupling fields.However,it is well blocked within the considered frequency region in the same direction of the coupling fields because of destruction of the EIT.Such selectable optical nonreciprocity and isolation for discrete signals may be greatly useful in controlling signal transmission and realizing selective optical isolation functions.展开更多
A scheme is proposed for tunable all-optical switching based on the double-dark states in a five-level atom-cavity system. In the scheme, the output signal light of the reflection and the transmission channels can be ...A scheme is proposed for tunable all-optical switching based on the double-dark states in a five-level atom-cavity system. In the scheme, the output signal light of the reflection and the transmission channels can be switched on or off by manipulating the control field. When the control light is coupled to the atom-cavity system, the input signal light is reflected by the cavity. Thus, there is no direct coupling between the control light and the signal light. Furthermore, the position of the double-dark states can be changed by adjusting the coherent field, and,thus, the switching in our scheme is tunable. By presenting the numerical calculations of the switching efficiency,we show that this type of the interaction-free all-optical switching can be realized with high switching efficiency.展开更多
基金sponsored by the National Natural Science Foundation of China(61804054)the Natural Science Foundation of Shanghai(18ZR1410400)+2 种基金the Shanghai Sailing Program(17YF1403300)the Shanghai Aerospace Science and Technology Innovation Fundation(SISP2018)the Shanghai Aerospace Science and Technology Innovation Fund(SAST2019-067)。
文摘Flexible aqueous Ni//Zn batteries have attracted much attention as promising candidates for energy storage in the field of flexible electronics.However,the Ni-based cathodes still face the challenges of poor conductivity,confined charge/mass transfer,and non-flexibility.In this work,we designed a hollow tubular structure consisting of a conductive silver nanowire (Ag NW) wrapped by active Ni Co layered double hydroxide (LDH),for enhancing the electrical conductivity,improving the charge/mass transfer kinetics,and facilitating the ion penetration.By optimizing the contents of Ni,Co and Ag NW,the Ni_(4)Co LDH@Ag_(1.5)NW composite shows a maximum specific capacity of 115.83 m Ah g^(-1)at 0.1 A g^(-1)measured in a two-electrode system.Highlightingly,the flexible aqueous Ni//Zn battery assembled by Ni_(4)Co LDH@Ag_(1.5)NW interwoven with multi-walled carbon nanotube cathode and Zn foil anode realizes a high power density of 160μW cm^(-2)at the energy density of 23.14μWh cm^(-2),which is superior compared with those of oxide/hydroxide based devices and even higher than those of many carbon-based supercapacitors,showing its promising potentials for flexible energy storage applications.
基金supported by the National Natural Science Foundation of China(Nos.61835013,12034007,11874146,12274123)Natural Science Foundation of Shanghai(No.20ZR1414300)。
文摘Nitrogen-vacancy(NV)centers in diamond are progressively favored for room-temperature magnetic field measurement.The signal to noise ratio(SNR)optimization for NV diamond magnetometry generally concentrates on signal amplitude enhancement rather than efficient noise processing.Here,we report a compound filter system combining a wavelet denoising method and an adaptive filter for the realization of an efficient weak magnetic measurement with a high SNR.It allows enhanced magnetic field measurement with an average SNR enhancement of 17.80 dB at 50 nT within 500 mHz to 100 Hz and14.76 dB at 500 mHz within 50 n T to 1100 n T.The introduction of this system in NV diamond magnetometry is aimed to improve signal quality by effectively eliminating the noise and retaining ideal signals.
基金supported by the National Natural Science Foundation of China (Nos. 11874146, 11974109, and 12034007)
文摘Multi-band signal propagation and processing play an important role in quantum communications and quantum computing.In recent years,optical nonreciprocal devices such as an optical isolator and circulator are proposed via various configurations of atoms,metamaterials,nonlinear waveguides,etc.In this work,we investigate all-optical controlled nonreciprocity of multi-band optical signals in thermal atomic systems.Via introducing multiple strong coupling fields,nonreciprocal propagation of the probe field can happen at some separated frequency bands,which results from combination of the electromagnetically induced transparency(EIT) effect and atomic thermal motion.In the proposed configuration,the frequency shift resulting from atomic thermal motion takes converse effect on the probe field in the two opposite directions.In this way,the probe field can propagate almost transparently within some frequency bands of EIT windows in the opposite direction of the coupling fields.However,it is well blocked within the considered frequency region in the same direction of the coupling fields because of destruction of the EIT.Such selectable optical nonreciprocity and isolation for discrete signals may be greatly useful in controlling signal transmission and realizing selective optical isolation functions.
基金supported by the National Natural Sciences Foundation of China(Nos.11674094,11274112,91321101,and 61275215)the Fundamental Research Funds for the Central Universities(No.WM1313003)
文摘A scheme is proposed for tunable all-optical switching based on the double-dark states in a five-level atom-cavity system. In the scheme, the output signal light of the reflection and the transmission channels can be switched on or off by manipulating the control field. When the control light is coupled to the atom-cavity system, the input signal light is reflected by the cavity. Thus, there is no direct coupling between the control light and the signal light. Furthermore, the position of the double-dark states can be changed by adjusting the coherent field, and,thus, the switching in our scheme is tunable. By presenting the numerical calculations of the switching efficiency,we show that this type of the interaction-free all-optical switching can be realized with high switching efficiency.
