Metalenses have gained significant attention and have been widely utilized in optical systems for focusing and imaging,owing to their lightweight,high-integration,and exceptional-flexibility capabilities.Traditional d...Metalenses have gained significant attention and have been widely utilized in optical systems for focusing and imaging,owing to their lightweight,high-integration,and exceptional-flexibility capabilities.Traditional design methods neglect the coupling effect between adjacent meta-atoms,thus harming the practical performance of meta-devices.The existing physical/data-driven optimization algorithms can solve the above problems,but bring significant time costs or require a large number of data-sets.Here,we propose a physics-data-driven method employing an“intelligent optimizer”that enables us to adaptively modify the sizes of the meta-atom according to the sizes of its surrounding ones.The implementation of such a scheme effectively mitigates the undesired impact of local lattice coupling,and the proposed network model works well on thousands of data-sets with a validation loss of 3×10^(−3).Based on the“intelligent optimizer”,a 1-cm-diameter metalens is designed within 3 hours,and the experimental results show that the 1-mm-diameter metalens has a relative focusing efficiency of 93.4%(compared to the ideal focusing efficiency)and a Strehl ratio of 0.94.Compared to previous inverse design method,our method significantly boosts designing efficiency with five orders of magnitude reduction in time.More generally,it may set a new paradigm for devising large-aperture meta-devices.展开更多
Imaging polarimetry is one of the most widely used analytical technologies for object detection and analysis.To date,most metasurface-based polarimetry techniques are severely limited by narrow operating bandwidths an...Imaging polarimetry is one of the most widely used analytical technologies for object detection and analysis.To date,most metasurface-based polarimetry techniques are severely limited by narrow operating bandwidths and inevitable crosstalk,leading to detrimental effects on imaging quality and measurement accuracy.Here,we propose a crosstalkfree broadband achromatic full Stokes imaging polarimeter consisting of polarization-sensitive dielectric metalenses,implemented by the principle of polarization-dependent phase optimization.Compared with the single-polarization optimization method,the average crosstalk has been reduced over three times under incident light with arbitrary polarization ranging from 9μm to 12μm,which guarantees the measurement of the polarization state more precisely.The experimental results indicate that the designed polarization-sensitive metalenses can effectively eliminate the chromatic aberration with polarization selectivity and negligible crosstalk.The measured average relative errors are 7.08%,8.62%,7.15%,and 7.59%at 9.3,9.6,10.3,and 10.6μm,respectively.Simultaneously,the broadband full polarization imaging capability of the device is also verified.This work is expected to have potential applications in wavefront detection,remote sensing,light-field imaging,and so forth.展开更多
With inherent orthogonality,both the spin angular momentum(SAM)and orbital angular momentum(OAM)of photons have been utilized to expand the dimensions of quantum information,optical communications,and information proc...With inherent orthogonality,both the spin angular momentum(SAM)and orbital angular momentum(OAM)of photons have been utilized to expand the dimensions of quantum information,optical communications,and information processing,wherein simultaneous detection of SAMs and OAMs with a single element and a single-shot measurement is highly anticipated.Here,a single azimuthal-quadratic phase metasurface-based photonic momentum transformation(PMT)is illustrated and utilized for vortex recognition.Since different vortices are converted into focusing patterns with distinct azimuthal coordinates on a transverse plane through PMT,OAMs within a large mode space can be determined through a single-shot measurement.Moreover,spin-controlled dual-functional PMTs are proposed for simultaneous SAM and OAM sorting,which is implemented by a single spin-decoupled metasurface that merges both the geometric phase and dynamic phase.Interestingly,our proposed method can detect vectorial vortices with both phase and polarization singularities,as well as superimposed vortices with a certain interval step.Experimental results obtained at several wavelengths in the visible band exhibit good agreement with the numerical modeling.With the merits of ultracompact device size,simple optical configuration,and prominent vortex recognition ability,our approach may underpin the development of integrated and high-dimensional optical and quantum systems.展开更多
Achieving electromagnetic wave scattering manipulation in the multispectral and broad operation band has been a long pursuit in stealth applications. Here, we present an approach by using single-layer metasurfaces com...Achieving electromagnetic wave scattering manipulation in the multispectral and broad operation band has been a long pursuit in stealth applications. Here, we present an approach by using single-layer metasurfaces composed of space-variant amorphous silicon ridges tiled on a metallic mirror, to generate high-efficiency dual-band and ultra-wideband photonic spin-orbit interaction and geometric phase. Two scattering engineered metasurfaces have been designed to reduce specular reflection;the first one can suppress both specular reflectances at 1.05–1.08 μm and 5–12 μm below 10%. The second one is designed for an ultra-broadband of 4.6–14 μm, which is actually implemented by cleverly connecting two bands of 4.6–6.1 μm and 6.1–14 μm. Furthermore, the presented structures exhibit low thermal emission at the same time due to the low absorption loss of silicon in the infrared spectrum, which can be regarded as an achievement of laser–infrared compatible camouflage.We believe the proposed strategy may open a new route to implement multispectral electromagnetic modulation and multiphysical engineering applications.展开更多
基金supported by the National Key Research and Development Program (2021YFA1401000)the National Natural Science Foundation of China (No.61975210,62175242 and 62305345)Sichuan Science and Technology Program (2020YFJ0001).
文摘Metalenses have gained significant attention and have been widely utilized in optical systems for focusing and imaging,owing to their lightweight,high-integration,and exceptional-flexibility capabilities.Traditional design methods neglect the coupling effect between adjacent meta-atoms,thus harming the practical performance of meta-devices.The existing physical/data-driven optimization algorithms can solve the above problems,but bring significant time costs or require a large number of data-sets.Here,we propose a physics-data-driven method employing an“intelligent optimizer”that enables us to adaptively modify the sizes of the meta-atom according to the sizes of its surrounding ones.The implementation of such a scheme effectively mitigates the undesired impact of local lattice coupling,and the proposed network model works well on thousands of data-sets with a validation loss of 3×10^(−3).Based on the“intelligent optimizer”,a 1-cm-diameter metalens is designed within 3 hours,and the experimental results show that the 1-mm-diameter metalens has a relative focusing efficiency of 93.4%(compared to the ideal focusing efficiency)and a Strehl ratio of 0.94.Compared to previous inverse design method,our method significantly boosts designing efficiency with five orders of magnitude reduction in time.More generally,it may set a new paradigm for devising large-aperture meta-devices.
基金Sichuan Science and Technology Program(2020YFJ0001)the National Natural Science Foundation of China(61975210,62222513)+1 种基金National Key Research and Development Program(SQ2021YFA1400121)China Postdoctoral Science Foundation(2021T140670)
文摘Imaging polarimetry is one of the most widely used analytical technologies for object detection and analysis.To date,most metasurface-based polarimetry techniques are severely limited by narrow operating bandwidths and inevitable crosstalk,leading to detrimental effects on imaging quality and measurement accuracy.Here,we propose a crosstalkfree broadband achromatic full Stokes imaging polarimeter consisting of polarization-sensitive dielectric metalenses,implemented by the principle of polarization-dependent phase optimization.Compared with the single-polarization optimization method,the average crosstalk has been reduced over three times under incident light with arbitrary polarization ranging from 9μm to 12μm,which guarantees the measurement of the polarization state more precisely.The experimental results indicate that the designed polarization-sensitive metalenses can effectively eliminate the chromatic aberration with polarization selectivity and negligible crosstalk.The measured average relative errors are 7.08%,8.62%,7.15%,and 7.59%at 9.3,9.6,10.3,and 10.6μm,respectively.Simultaneously,the broadband full polarization imaging capability of the device is also verified.This work is expected to have potential applications in wavefront detection,remote sensing,light-field imaging,and so forth.
基金the National Natural Science Funds of China under Grant Nos.61875253 and 61975210 and the Chinese Academy of Sciences Youth Innovation Promotion Association under Grant No.2019371.
文摘With inherent orthogonality,both the spin angular momentum(SAM)and orbital angular momentum(OAM)of photons have been utilized to expand the dimensions of quantum information,optical communications,and information processing,wherein simultaneous detection of SAMs and OAMs with a single element and a single-shot measurement is highly anticipated.Here,a single azimuthal-quadratic phase metasurface-based photonic momentum transformation(PMT)is illustrated and utilized for vortex recognition.Since different vortices are converted into focusing patterns with distinct azimuthal coordinates on a transverse plane through PMT,OAMs within a large mode space can be determined through a single-shot measurement.Moreover,spin-controlled dual-functional PMTs are proposed for simultaneous SAM and OAM sorting,which is implemented by a single spin-decoupled metasurface that merges both the geometric phase and dynamic phase.Interestingly,our proposed method can detect vectorial vortices with both phase and polarization singularities,as well as superimposed vortices with a certain interval step.Experimental results obtained at several wavelengths in the visible band exhibit good agreement with the numerical modeling.With the merits of ultracompact device size,simple optical configuration,and prominent vortex recognition ability,our approach may underpin the development of integrated and high-dimensional optical and quantum systems.
基金National Natural Science Foundation of China(NSFC)(61575201,61622508,61822511)
文摘Achieving electromagnetic wave scattering manipulation in the multispectral and broad operation band has been a long pursuit in stealth applications. Here, we present an approach by using single-layer metasurfaces composed of space-variant amorphous silicon ridges tiled on a metallic mirror, to generate high-efficiency dual-band and ultra-wideband photonic spin-orbit interaction and geometric phase. Two scattering engineered metasurfaces have been designed to reduce specular reflection;the first one can suppress both specular reflectances at 1.05–1.08 μm and 5–12 μm below 10%. The second one is designed for an ultra-broadband of 4.6–14 μm, which is actually implemented by cleverly connecting two bands of 4.6–6.1 μm and 6.1–14 μm. Furthermore, the presented structures exhibit low thermal emission at the same time due to the low absorption loss of silicon in the infrared spectrum, which can be regarded as an achievement of laser–infrared compatible camouflage.We believe the proposed strategy may open a new route to implement multispectral electromagnetic modulation and multiphysical engineering applications.
