Chiral sum-frequency generation(SFG)has proven to be a versatile spectroscopic and imaging tool for probing chirality.However,due to polarization restriction,the conventional chiral SFG microscopes have mostly adopted...Chiral sum-frequency generation(SFG)has proven to be a versatile spectroscopic and imaging tool for probing chirality.However,due to polarization restriction,the conventional chiral SFG microscopes have mostly adopted noncollinear beam configurations,which only partially cover the aperture of microscope and strongly spoil the spatial resolution.In this study,we report the first experimental demonstration of collinear chiral SFG microscopy,which fundamentally supports diffraction-limited resolution.This advancement is attributed to the collinear focus of a radially polarized vectorial beam and a linearly polarized(LP)beam.The tightly focused vectorial beam has a very strong longitudinal component,which interacts with the LP beam and produces the chiral SFG.The collinear configuration can utilize the full aperture and thus push the spatial resolution close to the diffraction limit.This technique can potentially boost the understanding of chiral systems.展开更多
The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual par...The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual particle.Here we report on a robust and high-speed rotation control in optical tweezers by using a novel linear polarization synthesis based on optical heterodyne interference between two circularly polarized lights with opposite handedness.The synthesized linear polarization can be rotated in a hopping-free scheme at arbitrary speed determined electronically by the heterodyne frequency between two laser fields.The experimental demonstration of a trapped vaterite particle in water shows that the precisely controlled rotation frequency of 300 Hz can be achieved.The proposed method will find promising applications in optically driven micro-gears,fluidic pumps and rotational micro-rheology.展开更多
Structured illumination microscopy(SIM)has been widely applied in the superresolution imaging of subcellular dynamics in live cells.Higher spatial resolution is expected for the observation of finer structures.However...Structured illumination microscopy(SIM)has been widely applied in the superresolution imaging of subcellular dynamics in live cells.Higher spatial resolution is expected for the observation of finer structures.However,further increasing spatial resolution in SIM under the condition of strong background and noise levels remains challenging.Here,we report a method to achieve deep resolution enhancement of SIM by combining an untrained neural network with an alternating direction method of multipliers(ADMM)framework,i.e.,ADMM-DRE-SIM.By exploiting the implicit image priors in the neural network and the Hessian prior in the ADMM framework associated with the optical transfer model of SIM,ADMM-DRE-SIM can further realize the spatial frequency extension without the requirement of training datasets.Moreover,an image degradation model containing the convolution with equivalent point spread function of SIM and additional background map is utilized to suppress the strong background while keeping the structure fidelity.Experimental results by imaging tubulins and actins show that ADMM-DRE-SIM can obtain the resolution enhancement by a factor of∼1.6 compared to conventional SIM,evidencing the promising applications of ADMM-DRE-SIM in superresolution biomedical imaging.展开更多
Light-sheet fluorescence microscopy(LSFM)has played an important role in bio-imaging due to its advantages of high photon efficiency,fast speed,and long-term imaging capabilities.The perpendicular layout between LSFM ...Light-sheet fluorescence microscopy(LSFM)has played an important role in bio-imaging due to its advantages of high photon efficiency,fast speed,and long-term imaging capabilities.The perpendicular layout between LSFM excitation and detection often limits the 3D resolutions as well as their isotropy.Here,we report on a reflective type light-sheet microscope with a mini-prism used as an optical path reflector.The conventional high NA objectives can be used both in excitation and detection with this design.Isotropic resolutions in 3D down to300 nm could be achieved without deconvolution.The proposed method also enables easy transform of a conventional fluorescence microscope to high performance light-sheet microscopy.展开更多
The emergence of super-resolution(SR)fluorescence microscopy has rejuvenated the search for new cellular substructures.However,SR fluorescence microscopy achieves high contrast at the expense of a holistic view of the...The emergence of super-resolution(SR)fluorescence microscopy has rejuvenated the search for new cellular substructures.However,SR fluorescence microscopy achieves high contrast at the expense of a holistic view of the interacting partners and surrounding environment.Thus,we developed SR fluorescence-assisted diffraction computational tomography(SR-FACT),which combines label-free three-dimensional optical diffraction tomography(ODT)with two-dimensional fluorescence Hessian structured illumination microscopy.The ODT module is capable of resolving the mitochondria,lipid droplets,the nuclear membrane,chromosomes,the tubular endoplasmic reticulum,and lysosomes.Using dual-mode correlated live-cell imaging for a prolonged period of time,we observed novel subcellular structures named dark-vacuole bodies,the majority of which originate from densely populated perinuclear regions,and intensively interact with organelles such as the mitochondria and the nuclear membrane before ultimately collapsing into the plasma membrane.This work demonstrates the unique capabilities of SR-FACT,which suggests its wide applicability in cell biology in general.展开更多
Achieving strong coupling between plasmonic oscillators can significantly modulate their intrinsic optical properties.Here,we report the direct observation of ultrafast plasmonic hot electron transfer from an Au grati...Achieving strong coupling between plasmonic oscillators can significantly modulate their intrinsic optical properties.Here,we report the direct observation of ultrafast plasmonic hot electron transfer from an Au grating array to an MoS_(2) monolayer in the strong coupling regime between localized surface plasmons(LSPs)and surface plasmon polaritons(SPPs).By means of femtosecond pump-probe spectroscopy,the measured hot electron transfer time is approximately 40 fs with a maximum external quantum yield of 1.65%.Our results suggest that strong coupling between LSPs and SPPs has synergetic effects on the generation of plasmonic hot carriers,where SPPs with a unique nonradiative feature can act as an‘energy recycle bin’to reuse the radiative energy of LSPs and contribute to hot carrier generation.Coherent energy exchange between plasmonic modes in the strong coupling regime can further enhance the vertical electric field and promote the transfer of hot electrons between the Au grating and the MoS_(2) monolayer.Our proposed plasmonic strong coupling configuration overcomes the challenge associated with utilizing hot carriers and is instructive in terms of improving the performance of plasmonic opto-electronic devices.展开更多
A slow-light effect based on metamaterial-induced transparency(MIT)possesses great practical applications for integrated photonic devices.However,to date,only very weak slow-light effects have been obtained in metamat...A slow-light effect based on metamaterial-induced transparency(MIT)possesses great practical applications for integrated photonic devices.However,to date,only very weak slow-light effects have been obtained in metamaterials because of the intrinsic loss of metal.Moreover,no active control of slow-light has been achieved in metamaterials.Here,we report the realization of a giant slow-light effect on an ultrathin metasurface that consists of periodic arrays of gold nanoprism dimers with a thickness of 40 nm sandwiched between a multilayer-graphene micro-sheet/zinc oxide nanoparticle layer and a monolayer graphene/polycrystalline indium tin oxide layer.The strong field confinement of the plasmonic modes associated with the MIT ensures a tremendous reduction in the group velocity around the transparency window.A group index of more than 4×10^(3) is achieved,which is one order of magnitude greater than that of previous reports.A large tunable wavelength range of 120 nm is achieved around the center of the transparency window when the pump light intensity is only 1.5 kW cm^(-2).The response time is as fast as 42.3 ps.These results demonstrate the potential for the realization of various functional integrated photonic devices based on metasurfaces,such as all-optical buffers and all-optical switches.展开更多
Birefringence-involved phase matching is demonstrated to be a novel mechanism to generate transform limited solitary pulses in an ultrafast mode-locking fiber laser cavity with normal dispersion.
Perovskite-enabled optical devices have drawn intensive interest and have been considered promising candidates for integrated optoelectronic systems.As one of the important photonic functions,optical phase modulation ...Perovskite-enabled optical devices have drawn intensive interest and have been considered promising candidates for integrated optoelectronic systems.As one of the important photonic functions,optical phase modulation previously was demonstrated with perovskite substrate and complex refractive index engineering with laser scribing.Here we report on the new scheme of achieving efficient phase modulation by combining detour phase design with 40 nm ultrathin perovskite films composed of nanosized crystalline particles.Phase modulation was realized by binary amplitude patterning,which significantly simplifies the fabrication process.Perovskite nanocrystal films exhibit significantly weak ion migration effects under femtosecond laser writing,resulting in smooth edges along the laser ablated area and high diffractive optical quality.Fabrication of a detour-phased perovskite ultrathin planar lens with a diameter of 150μm using femtosecond laser scribing was experimentally demonstrated.A high-performance 3D focus was observed,and the fabrication showed a high tolerance with different laser writing powers.Furthermore,the high-quality imaging capability of perovskite ultrathin planar lenses with a suppressed background was also demonstrated.展开更多
In order to extract the quantitative three-dimensional(3-D)distribution of refractive index(RI)in live cells noninvasively,optical diffraction tomography(ODT)uses the non-ionizing light sources instead of x-rays to pe...In order to extract the quantitative three-dimensional(3-D)distribution of refractive index(RI)in live cells noninvasively,optical diffraction tomography(ODT)uses the non-ionizing light sources instead of x-rays to perform a computational holographic tomography.展开更多
The pixel size of a charge-coupled device(CCD)camera plays a major role in the image resolution,and the square pixels are attributed to the physical anisotropy of the sampling frequency.We synthesize the high sampling...The pixel size of a charge-coupled device(CCD)camera plays a major role in the image resolution,and the square pixels are attributed to the physical anisotropy of the sampling frequency.We synthesize the high sampling frequency directions from multiple frames acquired with different angles to enhance the resolution by 1.4×over conventional CCD orthogonal sampling.To directly demonstrate the improvement of frequency-domain diagonal extension(FDDE)microscopy,lens-free microscopy is used,as its resolution is dominantly determined by the pixel size.We demonstrate the resolution enhancement with a mouse skin histological specimen and a clinical blood smear sample.Further,FDDE is extended to lens-based photography with an ISO 12233 resolution target.This method paves a new way for enhancing the image resolution for a variety of imaging techniques in which the resolution is primarily limited by the sampling pixel size,for example,microscopy,photography,and spectroscopy.展开更多
Various super-resolution microscopy techniques have been presented to explore fine structures of biological specimens.However,the super-resolution capability is often achieved at the expense of reducing imaging speed ...Various super-resolution microscopy techniques have been presented to explore fine structures of biological specimens.However,the super-resolution capability is often achieved at the expense of reducing imaging speed by either point scanning or multiframe computation.The contradiction between spatial resolution and imaging speed seriously hampers the observation of high-speed dynamics of fine structures.To overcome this contradiction,here we propose and demonstrate a temporal compressive super-resolution microscopy(TCSRM)technique.This technique is to merge an enhanced temporal compressive microscopy and a deep-learning-based super-resolution image reconstruction,where the enhanced temporal compressive microscopy is utilized to improve the imaging speed,and the deep-learning-based super-resolution image reconstruction is used to realize the resolution enhancement.The high-speed super-resolution imaging ability of TCSRM with a frame rate of 1200 frames per second(fps)and spatial resolution of 100 nm is experimentally demonstrated by capturing the flowing fluorescent beads in microfluidic chip.Given the outstanding imaging performance with high-speed super-resolution,TCSRM provides a desired tool for the studies of high-speed dynamical behaviors in fine structures,especially in the biomedical field.展开更多
Compact micro-spectrometers have gained significant attention due to their ease of integration and real-time spectrum measurement capabilities.However,size reduction often compromises performance,particularly in resol...Compact micro-spectrometers have gained significant attention due to their ease of integration and real-time spectrum measurement capabilities.However,size reduction often compromises performance,particularly in resolution and measurable wavelength range.This work proposes a computational micro-spectrometer based on an ultra-thin(~250 nm)detour-phased graphene oxide planar lens with a sub-millimeter footprint,utilizing a spectral-to-spatial mapping method.The varying intensity pattern along the focal axis of the lens acts as a measurement signal,simplifying the system and enabling real-time spectrum acquisition.Combined with computational retrieval method,an input spectrum is reconstructed with a wavelength interval down to 5 nm,representing a 5-time improvement compared with the result when not using computational method.In an optical compartment of 200μm by 200μm by 450μm from lens profile to the detector surface,the ultracompact spectrometer achieves broad spectrum measurement covering the visible range(420−750 nm)with a wavelength interval of 15 nm.Our compact computational micro-spectrometer paves the way for integration into portable,handheld,and wearable devices,holding promise for diverse real-time applications like in-situ health monitoring(e.g.,tracking blood glucose levels),food quality assessment,and portable counterfeit detection.展开更多
基金supported by the Guangdong Major Project of Basic and Applied Basic Research (Grant No.2020B0301030009)the National Natural Science Foundation of China (Grant Nos.91750203,91850111,11174019,12004013,92150301,and 61322509)+1 种基金the Ministry of Science and Technology of China[National Basic Research Program of China (Grant No.2013CB921904)]the China Postdoctoral Science Foundation (Grant No.2020M680220).
文摘Chiral sum-frequency generation(SFG)has proven to be a versatile spectroscopic and imaging tool for probing chirality.However,due to polarization restriction,the conventional chiral SFG microscopes have mostly adopted noncollinear beam configurations,which only partially cover the aperture of microscope and strongly spoil the spatial resolution.In this study,we report the first experimental demonstration of collinear chiral SFG microscopy,which fundamentally supports diffraction-limited resolution.This advancement is attributed to the collinear focus of a radially polarized vectorial beam and a linearly polarized(LP)beam.The tightly focused vectorial beam has a very strong longitudinal component,which interacts with the LP beam and produces the chiral SFG.The collinear configuration can utilize the full aperture and thus push the spatial resolution close to the diffraction limit.This technique can potentially boost the understanding of chiral systems.
基金the National Natural Science Foundation of China(91750203 and 91850111)State Key Laboratory of Applied Optics,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences and the High-performance Computing Platform of Peking University.
文摘The rotation control of particles in optical tweezers is often subject to the spin or orbit angular momentum induced optical torque,which is susceptible to the mechanical and morphological properties of individual particle.Here we report on a robust and high-speed rotation control in optical tweezers by using a novel linear polarization synthesis based on optical heterodyne interference between two circularly polarized lights with opposite handedness.The synthesized linear polarization can be rotated in a hopping-free scheme at arbitrary speed determined electronically by the heterodyne frequency between two laser fields.The experimental demonstration of a trapped vaterite particle in water shows that the precisely controlled rotation frequency of 300 Hz can be achieved.The proposed method will find promising applications in optically driven micro-gears,fluidic pumps and rotational micro-rheology.
基金supported by the National Natural Science Foundation of China(Grant Nos.12274129,12274139,12074121,92150301,62105101,62175066,and 12034008)the Science and Technology Commission of Shanghai Municipality(Grant Nos.21XD1400900,20ZR1417100,and 21JM0010700).
文摘Structured illumination microscopy(SIM)has been widely applied in the superresolution imaging of subcellular dynamics in live cells.Higher spatial resolution is expected for the observation of finer structures.However,further increasing spatial resolution in SIM under the condition of strong background and noise levels remains challenging.Here,we report a method to achieve deep resolution enhancement of SIM by combining an untrained neural network with an alternating direction method of multipliers(ADMM)framework,i.e.,ADMM-DRE-SIM.By exploiting the implicit image priors in the neural network and the Hessian prior in the ADMM framework associated with the optical transfer model of SIM,ADMM-DRE-SIM can further realize the spatial frequency extension without the requirement of training datasets.Moreover,an image degradation model containing the convolution with equivalent point spread function of SIM and additional background map is utilized to suppress the strong background while keeping the structure fidelity.Experimental results by imaging tubulins and actins show that ADMM-DRE-SIM can obtain the resolution enhancement by a factor of∼1.6 compared to conventional SIM,evidencing the promising applications of ADMM-DRE-SIM in superresolution biomedical imaging.
基金National Key Research and Development Program of China(2022YFC3401100,2022YFF0712500)Guangdong Major Project of Basic and Applied Basic Research(2020B0301030009)+5 种基金National Natural Science Foundation of China(12204017,12004012,12004013,12041602,91750203,91850111,92150301)China Postdoctoral Science Foundation(2020M680220,2020M680230)Clinical Medicine Plus X-Young Scholars ProjectPeking UniversityFundamental Research Funds for the Central UniversitiesHigh-performance Computing Platform of Peking University。
文摘Light-sheet fluorescence microscopy(LSFM)has played an important role in bio-imaging due to its advantages of high photon efficiency,fast speed,and long-term imaging capabilities.The perpendicular layout between LSFM excitation and detection often limits the 3D resolutions as well as their isotropy.Here,we report on a reflective type light-sheet microscope with a mini-prism used as an optical path reflector.The conventional high NA objectives can be used both in excitation and detection with this design.Isotropic resolutions in 3D down to300 nm could be achieved without deconvolution.The proposed method also enables easy transform of a conventional fluorescence microscope to high performance light-sheet microscopy.
基金supported by grants from the National Natural Science Foundation of China(91750203,91854112,81925022,31521062,91850111,31901061,and 31327901)the National Science and Technology Major Project Programme(2016YFA0500400,2017YFC0110203,and SQ2016YFJC040028)+3 种基金the Beijing Natural Science Foundation(L172003,7152079,and 5194026)the National Postdoctoral Program for Innovative Talents(BX201800008)the China Postdoctoral Science Foundation(2019M650329)the High-performance Computing Platform of Peking University.
文摘The emergence of super-resolution(SR)fluorescence microscopy has rejuvenated the search for new cellular substructures.However,SR fluorescence microscopy achieves high contrast at the expense of a holistic view of the interacting partners and surrounding environment.Thus,we developed SR fluorescence-assisted diffraction computational tomography(SR-FACT),which combines label-free three-dimensional optical diffraction tomography(ODT)with two-dimensional fluorescence Hessian structured illumination microscopy.The ODT module is capable of resolving the mitochondria,lipid droplets,the nuclear membrane,chromosomes,the tubular endoplasmic reticulum,and lysosomes.Using dual-mode correlated live-cell imaging for a prolonged period of time,we observed novel subcellular structures named dark-vacuole bodies,the majority of which originate from densely populated perinuclear regions,and intensively interact with organelles such as the mitochondria and the nuclear membrane before ultimately collapsing into the plasma membrane.This work demonstrates the unique capabilities of SR-FACT,which suggests its wide applicability in cell biology in general.
基金supported by the National Key Research and Development Program of China(Grant No.2017YFA0205700)National Basic Research Program of China(Grant Nos.2015CB932403,2017YFA0206000)+4 种基金National Science Foundation of China(Grant Nos.11674012,61422501,11374023,61521004 and 21790364)Beijing Natural Science Foundation(Grant No.L140007)Foundation for the Author of National Excellent Doctoral Dissertation of PR China(Grant No.201420)National Program for Support of Top-notch Young Professionals(Grant No.W02070003)Ministry of Education Singapore under Grant No.MOE2015-T2-2-043.
文摘Achieving strong coupling between plasmonic oscillators can significantly modulate their intrinsic optical properties.Here,we report the direct observation of ultrafast plasmonic hot electron transfer from an Au grating array to an MoS_(2) monolayer in the strong coupling regime between localized surface plasmons(LSPs)and surface plasmon polaritons(SPPs).By means of femtosecond pump-probe spectroscopy,the measured hot electron transfer time is approximately 40 fs with a maximum external quantum yield of 1.65%.Our results suggest that strong coupling between LSPs and SPPs has synergetic effects on the generation of plasmonic hot carriers,where SPPs with a unique nonradiative feature can act as an‘energy recycle bin’to reuse the radiative energy of LSPs and contribute to hot carrier generation.Coherent energy exchange between plasmonic modes in the strong coupling regime can further enhance the vertical electric field and promote the transfer of hot electrons between the Au grating and the MoS_(2) monolayer.Our proposed plasmonic strong coupling configuration overcomes the challenge associated with utilizing hot carriers and is instructive in terms of improving the performance of plasmonic opto-electronic devices.
基金This work was supported by the 973 Program of China under grant nos.2013CB328704 and 2014CB921003the National Natural Science Foundation of China under grant nos.11225417,61475003,11134001,11121091,and 90921008.
文摘A slow-light effect based on metamaterial-induced transparency(MIT)possesses great practical applications for integrated photonic devices.However,to date,only very weak slow-light effects have been obtained in metamaterials because of the intrinsic loss of metal.Moreover,no active control of slow-light has been achieved in metamaterials.Here,we report the realization of a giant slow-light effect on an ultrathin metasurface that consists of periodic arrays of gold nanoprism dimers with a thickness of 40 nm sandwiched between a multilayer-graphene micro-sheet/zinc oxide nanoparticle layer and a monolayer graphene/polycrystalline indium tin oxide layer.The strong field confinement of the plasmonic modes associated with the MIT ensures a tremendous reduction in the group velocity around the transparency window.A group index of more than 4×10^(3) is achieved,which is one order of magnitude greater than that of previous reports.A large tunable wavelength range of 120 nm is achieved around the center of the transparency window when the pump light intensity is only 1.5 kW cm^(-2).The response time is as fast as 42.3 ps.These results demonstrate the potential for the realization of various functional integrated photonic devices based on metasurfaces,such as all-optical buffers and all-optical switches.
文摘Birefringence-involved phase matching is demonstrated to be a novel mechanism to generate transform limited solitary pulses in an ultrafast mode-locking fiber laser cavity with normal dispersion.
基金Guangdong Major Project of Basic and Applied Basic Research(2020B0301030009)National Natural Science Foundation of China(12004012,12004013,12041602,91750203,91850111,92150301)+1 种基金China Postdoctoral Science Foundation(2020M680220,2020M680230)National Key Research and Development Program of China(2018YFA0306302)。
文摘Perovskite-enabled optical devices have drawn intensive interest and have been considered promising candidates for integrated optoelectronic systems.As one of the important photonic functions,optical phase modulation previously was demonstrated with perovskite substrate and complex refractive index engineering with laser scribing.Here we report on the new scheme of achieving efficient phase modulation by combining detour phase design with 40 nm ultrathin perovskite films composed of nanosized crystalline particles.Phase modulation was realized by binary amplitude patterning,which significantly simplifies the fabrication process.Perovskite nanocrystal films exhibit significantly weak ion migration effects under femtosecond laser writing,resulting in smooth edges along the laser ablated area and high diffractive optical quality.Fabrication of a detour-phased perovskite ultrathin planar lens with a diameter of 150μm using femtosecond laser scribing was experimentally demonstrated.A high-performance 3D focus was observed,and the fabrication showed a high tolerance with different laser writing powers.Furthermore,the high-quality imaging capability of perovskite ultrathin planar lenses with a suppressed background was also demonstrated.
文摘In order to extract the quantitative three-dimensional(3-D)distribution of refractive index(RI)in live cells noninvasively,optical diffraction tomography(ODT)uses the non-ionizing light sources instead of x-rays to perform a computational holographic tomography.
基金This work was supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.31971376,61705252,61729501,91750203,and 51720105015)the Beijing Natural Science Foundation(Grant No.JQ18019)+2 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20170388)Australia-China Joint Research Centre for Point-of-Care Testing(Grant Nos.ACSRF65827,SQ2017YFGH001190)Science and Technology Innovation Commission of Shenzhen(Grant No.KQTD20170810110913065).The authors declare that there are no conflicts of interest regarding the publication of this article.
文摘The pixel size of a charge-coupled device(CCD)camera plays a major role in the image resolution,and the square pixels are attributed to the physical anisotropy of the sampling frequency.We synthesize the high sampling frequency directions from multiple frames acquired with different angles to enhance the resolution by 1.4×over conventional CCD orthogonal sampling.To directly demonstrate the improvement of frequency-domain diagonal extension(FDDE)microscopy,lens-free microscopy is used,as its resolution is dominantly determined by the pixel size.We demonstrate the resolution enhancement with a mouse skin histological specimen and a clinical blood smear sample.Further,FDDE is extended to lens-based photography with an ISO 12233 resolution target.This method paves a new way for enhancing the image resolution for a variety of imaging techniques in which the resolution is primarily limited by the sampling pixel size,for example,microscopy,photography,and spectroscopy.
基金the National Natural Science Foundation of China(91850202,92150301,12074121,62105101,62175066,11727810,12034008,12274129,12274139)Science and Technology Commission of Shanghai Municipality(21XD1400900,20ZR1417100,21JM0010700).
文摘Various super-resolution microscopy techniques have been presented to explore fine structures of biological specimens.However,the super-resolution capability is often achieved at the expense of reducing imaging speed by either point scanning or multiframe computation.The contradiction between spatial resolution and imaging speed seriously hampers the observation of high-speed dynamics of fine structures.To overcome this contradiction,here we propose and demonstrate a temporal compressive super-resolution microscopy(TCSRM)technique.This technique is to merge an enhanced temporal compressive microscopy and a deep-learning-based super-resolution image reconstruction,where the enhanced temporal compressive microscopy is utilized to improve the imaging speed,and the deep-learning-based super-resolution image reconstruction is used to realize the resolution enhancement.The high-speed super-resolution imaging ability of TCSRM with a frame rate of 1200 frames per second(fps)and spatial resolution of 100 nm is experimentally demonstrated by capturing the flowing fluorescent beads in microfluidic chip.Given the outstanding imaging performance with high-speed super-resolution,TCSRM provides a desired tool for the studies of high-speed dynamical behaviors in fine structures,especially in the biomedical field.
基金funded by National Key Research and Development Program of China(2022YFF0712500,2022YFC3401100)Guangdong Major Project of Basic and Applied Basic Research No.2020B0301030009+4 种基金the National Natural Science Foundation of China(12004012,92150301,91750203,12041602,91850111,and 12004013)the China Postdoctoral Science Foundation(2020M680230,2020M680220)The author would like to thank the High-performance Computing Platform of Peking UniversityThis work was also supported by Australia Research Council(Grant No.DP220100603,FT210100806,FT220100559)Industrial Transformation Training Centres scheme(Grant No.IC180100005),Linkage Project scheme(LP210200345).
文摘Compact micro-spectrometers have gained significant attention due to their ease of integration and real-time spectrum measurement capabilities.However,size reduction often compromises performance,particularly in resolution and measurable wavelength range.This work proposes a computational micro-spectrometer based on an ultra-thin(~250 nm)detour-phased graphene oxide planar lens with a sub-millimeter footprint,utilizing a spectral-to-spatial mapping method.The varying intensity pattern along the focal axis of the lens acts as a measurement signal,simplifying the system and enabling real-time spectrum acquisition.Combined with computational retrieval method,an input spectrum is reconstructed with a wavelength interval down to 5 nm,representing a 5-time improvement compared with the result when not using computational method.In an optical compartment of 200μm by 200μm by 450μm from lens profile to the detector surface,the ultracompact spectrometer achieves broad spectrum measurement covering the visible range(420−750 nm)with a wavelength interval of 15 nm.Our compact computational micro-spectrometer paves the way for integration into portable,handheld,and wearable devices,holding promise for diverse real-time applications like in-situ health monitoring(e.g.,tracking blood glucose levels),food quality assessment,and portable counterfeit detection.