Multidimensional-engineering chalcogenide glasses is widely explored to construct various infrared photonic devices,with their surface as a key dimension for wavefront control.Here,we demonstrate direct patterning hig...Multidimensional-engineering chalcogenide glasses is widely explored to construct various infrared photonic devices,with their surface as a key dimension for wavefront control.Here,we demonstrate direct patterning high-aspect-ratio microstructures on the surface of chalcogenide glasses offers an efficient and robust method to manipulate longwave infrared radiations.Despite chalcogenide glass being considered soft in terms of its mechanical properties,we successfully fabricate high-aspect-ratio micropillars with a height of 8μm using optimized deep etching process,and we demonstrate a 2-mm-diameter all-chalcogenide metalens with a numerical aperture of 0.45 on the surface of a 1.5-mm-thick As2Se3 glass.Leveraging the exceptional longwave infrared(LWIR)transparency and moderate refractive index of As2Se3 glass,the all-chalcogenide metalens produces a focal spot size of~1.39λ0 with a focusing efficiency of 47%at the wavelength of 9.78μm,while also exhibiting high-resolution imaging capabilities.Our work provides a promising route to realize easy-to-fabricate,mass-producible planar infrared optics for compact,light-weight LWIR imaging systems.展开更多
The optoelectronic performance of quantum cascade detectors(QCDs)is highly sensitive to the design of the energy level structure,leading to the inability of a single structure to achieve broad wavelength tuning.To add...The optoelectronic performance of quantum cascade detectors(QCDs)is highly sensitive to the design of the energy level structure,leading to the inability of a single structure to achieve broad wavelength tuning.To address this issue,we propose and demonstrate a modular concept for very long wave infrared(VLWIR)QCDs based on a miniband diagonal transition scheme.The modular design makes the wavelength tuning only need to be adjusted for the absorption quantum well module rather than for the whole active region.Theoretical simulation shows that the wavelength tuning range is 39.6 meV(~14–30μm).To prove the feasibility of the scheme,three samples with different absorption well widths were fabricated and characterized.At 10 K,the response wavelengths of the three QCDs are 14,16,and 18μm,respectively,corresponding to responsivities and detectivities exceeding 2 mA/W and 1×10^(10)Jones.展开更多
Metasurfaces in the long wave infrared(LWIR)spectrum hold great potential for applications in ther-mal imaging,atmospheric remote sensing,and target identification,among others.In this study,we designed and experiment...Metasurfaces in the long wave infrared(LWIR)spectrum hold great potential for applications in ther-mal imaging,atmospheric remote sensing,and target identification,among others.In this study,we designed and experimentally demonstrated a 4 mm size,all-silicon metasurface metalens with large depth of focus opera-tional across a broadband range from 9µm to 11.5µm.The experimental results confirm effective focusing and imaging capabilities of the metalens in LWIR region,thus paving the way for practical LWIR applications of met-alens technology.展开更多
Recently,infrared polarization imaging technology has become a research hotspot due to its ability to better resolve the physicochemical properties of objects and significantly enhance the target characteristics.Howev...Recently,infrared polarization imaging technology has become a research hotspot due to its ability to better resolve the physicochemical properties of objects and significantly enhance the target characteristics.However,the traditional infrared polarization imaging is limited to similar imaging mechanism restrictions,and it is difficult to acquire the polarization information of a wide-area posture in real time.Therefore,we report a combination of hardware and software for super-wide-field-of-view long-wave infrared gaze polarization imaging technology.Utilizing the non-similar imaging theory and adopting the inter-lens coupling holographic linegrid infrared polarization device scheme,we designed the infrared gazing polarized lens with a field-of-view of over 160°.Based on the fusion of infrared intensity images and infrared polarization images,a multi-strategy detail feature extraction and fusion network is constructed.Super-wide-field-of-view(150°×120°),large face array(1040×830),detail-rich infrared fusion images are acquired during the test.We have accomplished the tasks of vehicle target detection and infrared camouflage target recognition efficiently using the fusion images,and verified the superiority of recognizing far-field targets.Our implementation should enable and empower applications in machine vision,intelligent driving,and target detection under complex environments.展开更多
We introduce a novel method to create mid-infrared(MIR)thermal emitters using fully epitaxial,metal-free structures.Through the strategic use of epsilon-near-zero(ENZ)thin films in InAs layers,we achieve a narrow-band...We introduce a novel method to create mid-infrared(MIR)thermal emitters using fully epitaxial,metal-free structures.Through the strategic use of epsilon-near-zero(ENZ)thin films in InAs layers,we achieve a narrow-band,wide-angle,and p-polarized thermal emission spectra.This approach,employing molecular beam epitaxy,circumvents the complexities associated with current layered structures and yields temperature-resistant emission wavelengths.Our findings contribute a promising route towards simpler,more efficient MIR optoelectronic devices.展开更多
Metalens technology has been applied extensively in miniaturized and integrated infrared imaging systems.However,due to the high phase dispersion of unit structures,metalens often exhibits chromatic aberration,making ...Metalens technology has been applied extensively in miniaturized and integrated infrared imaging systems.However,due to the high phase dispersion of unit structures,metalens often exhibits chromatic aberration,making broadband achromatic infrared imaging challenging to achieve.In this paper,six different unit structures based on chalcogenide glass are constructed,and their phase-dispersion parameters are analyzed to establish a database.On this basis,using chromatic aberration compensation and parameterized adjoint topology optimization,a broadband achromatic metalens with a numerical aperture of 0.5 is designed by arranging these six unit structures in the far-infrared band.Simulation results show that the metalens achieves near diffraction-limited focusing within the operating wavelength range of 9−11μm,demonstrating the good performance of achromatic aberration with flat focusing efficiency of 54%−58%across all wavelengths.展开更多
Since its invention,holography has been mostly applied at visible wavelengths in a variety of applications.Specifically,non-destructive testing of manufactured objects was a driver for developing holographic methods a...Since its invention,holography has been mostly applied at visible wavelengths in a variety of applications.Specifically,non-destructive testing of manufactured objects was a driver for developing holographic methods and all related ones based on the speckle pattern recording.One substantial limitation of holographic non-destructive testing is the setup stability requirements directly related to the laser wavelength.This observation has driven some works for 15 years:developing holography at wavelengths much longer than visible ones.In this paper,we will first review researches carried out in the infrared,mostly digital holography at thermal infrared wavelengths around 10 micrometers.We will discuss the advantages of using such wavelengths and show different examples of applications.In nondestructive testing,large wavelengths allow using digital holography in perturbed environments on large objects and measure large deformations,typical of the aerospace domain.Other astonishing applications such as reconstructing scenes through smoke and flames were proposed.When moving further in the spectrum,digital holography with so-called Terahertz waves(up to 3 millimeters wavelength)has also been studied.The main advantage here is that these waves easily penetrate some materials.Therefore,one can envisage Terahertz digital holography to reconstruct the amplitude and phase of visually opaque objects.We review some cases in which Terahertz digital holography has shown potential in biomedical and industrial applications.We will also address some fundamental bottlenecks that prevent fully benefiting from the advantages of digital holography when increasing the wavelength.展开更多
<div style="text-align:justify;"> In this paper, we report a single-mode Fabry-Pérot long wave infrared quantum cascade lasers based on the double phonon resonance active region design. For room t...<div style="text-align:justify;"> In this paper, we report a single-mode Fabry-Pérot long wave infrared quantum cascade lasers based on the double phonon resonance active region design. For room temperature CW operation, the wafer with 35 stages was processed into buried heterostructure lasers. For a 4 mm long and 13 μm wide laser with high-reflectivity (HR) coating on the rear facet, continuous wave output power of 43 mW at 288 K and 5 mW at 303 K is obtained with threshold current densities of 2.17 and 2.7 kA/cm2. The lasing wavelength is around 10.5 μm. Single mode emission was observed for this particular device over the whole investigated current and temperature range. </div>展开更多
Continuous wave（CW） operation of long wave infrared（LWIR） quantum cascade lasers（QCLs） is achieved up to a temperature of 303 K. For room temperature CW operation, the wafer with 35 stages was processed into bur...Continuous wave（CW） operation of long wave infrared（LWIR） quantum cascade lasers（QCLs） is achieved up to a temperature of 303 K. For room temperature CW operation, the wafer with 35 stages was processed into buried heterostructure lasers. For a 2-mm-long and 10-μm-wide laser with high-reflectivity（HR） coating on the rear facet, CW output power of 45 m W at 283 K and 9 m W at 303 K is obtained. The lasing wavelength is around 9.4 μm locating in the LWIR spectrum range.展开更多
基金supported by National Natural Science Foundation of China(Grant No.62105172)Natural Science Foundation of Zhejiang Province(Grant No.LDT23F05015F05,LDT23F05011F05).
文摘Multidimensional-engineering chalcogenide glasses is widely explored to construct various infrared photonic devices,with their surface as a key dimension for wavefront control.Here,we demonstrate direct patterning high-aspect-ratio microstructures on the surface of chalcogenide glasses offers an efficient and robust method to manipulate longwave infrared radiations.Despite chalcogenide glass being considered soft in terms of its mechanical properties,we successfully fabricate high-aspect-ratio micropillars with a height of 8μm using optimized deep etching process,and we demonstrate a 2-mm-diameter all-chalcogenide metalens with a numerical aperture of 0.45 on the surface of a 1.5-mm-thick As2Se3 glass.Leveraging the exceptional longwave infrared(LWIR)transparency and moderate refractive index of As2Se3 glass,the all-chalcogenide metalens produces a focal spot size of~1.39λ0 with a focusing efficiency of 47%at the wavelength of 9.78μm,while also exhibiting high-resolution imaging capabilities.Our work provides a promising route to realize easy-to-fabricate,mass-producible planar infrared optics for compact,light-weight LWIR imaging systems.
基金supported by the National Natural Science Foundation of China(Nos.61835011,62335015,12393830,62222408,and 12274404)the Key Program of the Chinese Academy of Sciences(No.XDB43000000)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2022112)。
文摘The optoelectronic performance of quantum cascade detectors(QCDs)is highly sensitive to the design of the energy level structure,leading to the inability of a single structure to achieve broad wavelength tuning.To address this issue,we propose and demonstrate a modular concept for very long wave infrared(VLWIR)QCDs based on a miniband diagonal transition scheme.The modular design makes the wavelength tuning only need to be adjusted for the absorption quantum well module rather than for the whole active region.Theoretical simulation shows that the wavelength tuning range is 39.6 meV(~14–30μm).To prove the feasibility of the scheme,three samples with different absorption well widths were fabricated and characterized.At 10 K,the response wavelengths of the three QCDs are 14,16,and 18μm,respectively,corresponding to responsivities and detectivities exceeding 2 mA/W and 1×10^(10)Jones.
基金Supported by National Key R&D Program of China(2021YFA0715500)National Natural Science Foundation of China(NSFC)(12227901)+1 种基金Strategic Priority Research Program(B)of the Chinese Academy of Sciences(XDB0580000)Chinese Academy of Sciences President's In-ternational Fellowship Initiative(2021PT0007).
文摘Metasurfaces in the long wave infrared(LWIR)spectrum hold great potential for applications in ther-mal imaging,atmospheric remote sensing,and target identification,among others.In this study,we designed and experimentally demonstrated a 4 mm size,all-silicon metasurface metalens with large depth of focus opera-tional across a broadband range from 9µm to 11.5µm.The experimental results confirm effective focusing and imaging capabilities of the metalens in LWIR region,thus paving the way for practical LWIR applications of met-alens technology.
基金National Natural Science Foundation of China(62171467)Natural Science Foundation of Hebei Province(F2021506004)。
文摘Recently,infrared polarization imaging technology has become a research hotspot due to its ability to better resolve the physicochemical properties of objects and significantly enhance the target characteristics.However,the traditional infrared polarization imaging is limited to similar imaging mechanism restrictions,and it is difficult to acquire the polarization information of a wide-area posture in real time.Therefore,we report a combination of hardware and software for super-wide-field-of-view long-wave infrared gaze polarization imaging technology.Utilizing the non-similar imaging theory and adopting the inter-lens coupling holographic linegrid infrared polarization device scheme,we designed the infrared gazing polarized lens with a field-of-view of over 160°.Based on the fusion of infrared intensity images and infrared polarization images,a multi-strategy detail feature extraction and fusion network is constructed.Super-wide-field-of-view(150°×120°),large face array(1040×830),detail-rich infrared fusion images are acquired during the test.We have accomplished the tasks of vehicle target detection and infrared camouflage target recognition efficiently using the fusion images,and verified the superiority of recognizing far-field targets.Our implementation should enable and empower applications in machine vision,intelligent driving,and target detection under complex environments.
文摘We introduce a novel method to create mid-infrared(MIR)thermal emitters using fully epitaxial,metal-free structures.Through the strategic use of epsilon-near-zero(ENZ)thin films in InAs layers,we achieve a narrow-band,wide-angle,and p-polarized thermal emission spectra.This approach,employing molecular beam epitaxy,circumvents the complexities associated with current layered structures and yields temperature-resistant emission wavelengths.Our findings contribute a promising route towards simpler,more efficient MIR optoelectronic devices.
文摘Metalens technology has been applied extensively in miniaturized and integrated infrared imaging systems.However,due to the high phase dispersion of unit structures,metalens often exhibits chromatic aberration,making broadband achromatic infrared imaging challenging to achieve.In this paper,six different unit structures based on chalcogenide glass are constructed,and their phase-dispersion parameters are analyzed to establish a database.On this basis,using chromatic aberration compensation and parameterized adjoint topology optimization,a broadband achromatic metalens with a numerical aperture of 0.5 is designed by arranging these six unit structures in the far-infrared band.Simulation results show that the metalens achieves near diffraction-limited focusing within the operating wavelength range of 9−11μm,demonstrating the good performance of achromatic aberration with flat focusing efficiency of 54%−58%across all wavelengths.
基金M.G.and Y.Z.acknowledge European Regional Development Fund/Wallonia region project(TERA4ALL)MG.and JF.V.acknowledge the support of ESA(GSTP project Contract No.22540/09/NL/SFe)EU(FP7 European project FANTOM ACP7-GA-2008-213457).
文摘Since its invention,holography has been mostly applied at visible wavelengths in a variety of applications.Specifically,non-destructive testing of manufactured objects was a driver for developing holographic methods and all related ones based on the speckle pattern recording.One substantial limitation of holographic non-destructive testing is the setup stability requirements directly related to the laser wavelength.This observation has driven some works for 15 years:developing holography at wavelengths much longer than visible ones.In this paper,we will first review researches carried out in the infrared,mostly digital holography at thermal infrared wavelengths around 10 micrometers.We will discuss the advantages of using such wavelengths and show different examples of applications.In nondestructive testing,large wavelengths allow using digital holography in perturbed environments on large objects and measure large deformations,typical of the aerospace domain.Other astonishing applications such as reconstructing scenes through smoke and flames were proposed.When moving further in the spectrum,digital holography with so-called Terahertz waves(up to 3 millimeters wavelength)has also been studied.The main advantage here is that these waves easily penetrate some materials.Therefore,one can envisage Terahertz digital holography to reconstruct the amplitude and phase of visually opaque objects.We review some cases in which Terahertz digital holography has shown potential in biomedical and industrial applications.We will also address some fundamental bottlenecks that prevent fully benefiting from the advantages of digital holography when increasing the wavelength.
文摘<div style="text-align:justify;"> In this paper, we report a single-mode Fabry-Pérot long wave infrared quantum cascade lasers based on the double phonon resonance active region design. For room temperature CW operation, the wafer with 35 stages was processed into buried heterostructure lasers. For a 4 mm long and 13 μm wide laser with high-reflectivity (HR) coating on the rear facet, continuous wave output power of 43 mW at 288 K and 5 mW at 303 K is obtained with threshold current densities of 2.17 and 2.7 kA/cm2. The lasing wavelength is around 10.5 μm. Single mode emission was observed for this particular device over the whole investigated current and temperature range. </div>
基金Project supported by the National Key Research And Development Program(No.2016YFB0402303)the National Natural Science Foundation of China(Nos.61435014,61627822,61574136,61774146,61674144,61404131)+1 种基金the Key Projects of Chinese Academy of Sciences(Nos.ZDRW-XH-2016-4,QYZDJ-SSW-JSC027)the Beijing Natural Science Foundation(No.4162060,4172060)
文摘Continuous wave（CW） operation of long wave infrared（LWIR） quantum cascade lasers（QCLs） is achieved up to a temperature of 303 K. For room temperature CW operation, the wafer with 35 stages was processed into buried heterostructure lasers. For a 2-mm-long and 10-μm-wide laser with high-reflectivity（HR） coating on the rear facet, CW output power of 45 m W at 283 K and 9 m W at 303 K is obtained. The lasing wavelength is around 9.4 μm locating in the LWIR spectrum range.
