The weak interlayer van der Waals(vdW) interactions in two-dimensional(2D) vdW materials enable sliding ferroelectricity as an effective strategy for modulating their intrinsic properties. In this work, we systematica...The weak interlayer van der Waals(vdW) interactions in two-dimensional(2D) vdW materials enable sliding ferroelectricity as an effective strategy for modulating their intrinsic properties. In this work, we systematically investigate the influence of interlayer sliding on the electronic behavior of PtSe_(2) using density functional theory(DFT) calculations. Our results demonstrate that interlayer sliding induces a pronounced photocurrent spanning the short-wavelength infrared to visible spectral ranges. Remarkably, under an applied gate voltage, the sliding ferroelectric PtSe_(2) exhibits anomalously enhanced photovoltaic performance and an ultrahigh extinction ratio.Transmission spectral analysis reveals that this phenomenon originates from band structure modifications driven by energy-level transitions. Furthermore, the observed photocurrent enhancement via sliding ferroelectricity demonstrates universality across diverse platinum-based optoelectronic devices. This study introduces a novel paradigm for tailoring the intrinsic characteristics of 2D vdW semiconductors, expanding the design space for next-generation ferroelectric materials in advanced optoelectronic applications.展开更多
Quantum well infrared photodetectors(QWIPs) based on intersubband transitions hold significant potential for high bandwidth operation. In this work, we establish a carrier transport optimization model incorporating el...Quantum well infrared photodetectors(QWIPs) based on intersubband transitions hold significant potential for high bandwidth operation. In this work, we establish a carrier transport optimization model incorporating electron injection at the emitter to investigate the carrier dynamics time and impedance spectroscopy in GaAs/AlGaAs QWIPs. Our findings provide novel evidence that the escape time of electrons is the key limiting factor for the 3-dB bandwidth of QWIPs. Moreover, to characterize the impact of carrier dynamics time and non-equilibrium space charge region on impedance, we developed an equivalent circuit model where depletion region resistance and capacitance are employed to describe non-equilibrium space charge region. Using this model, we discovered that under illumination, both net charge accumulation caused by variations in carrier dynamics times within quantum wells and changes in width of non-equilibrium space charge region exert different dominant influences on depletion region capacitance at various doping concentrations.展开更多
We design and fabricate a 128 × 128 AlGaAs/GaAs quantum well infrared photodetector focal plane array （FPA）. The device is achieved by metal organic chemical vapor deposition and GaAs integrated circuit process...We design and fabricate a 128 × 128 AlGaAs/GaAs quantum well infrared photodetector focal plane array （FPA）. The device is achieved by metal organic chemical vapor deposition and GaAs integrated circuit processing technology. A test structure of the photodetector with a mesa size of 300μm × 300μm is also made in order to obtain the device parameters. The measured dark current density at 77K is 1.5 × 10^-3A/cm^2 with a bias voltage of 2V. The peak of the responsivity spectrum is at 8.4μm,with a cutoff wavelength of 9μm. The blackbody detectivity is shown to be 3.95 × 10^8 （cm · Hz^1/2）/W. The final FPA is flip-chip bonded on a CMOS read-out integrated circuit. The infrared thermal images of some targets at room temperature background are successfully demonstrated at 80K operating temperature with a ratio of dead pixels of less than 1%.展开更多
Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral range.Despite the fact that they already achieved ...Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral range.Despite the fact that they already achieved notable success,the performance suffers from the thermionic emission of electrons from the quantum dots at elevated temperatures resulting in a decreasing responsivity.In order to provide an efficient carrier injection at high temperatures,quantum dot infrared photodetectors can be separated into two parts:an injection part and a detection part,so that each part can be separately optimized.In order to integrate such functionality into a device,a new class of quantum dot infrared photodetectors using quantum dot molecules will be introduced.In addition to a general discussion simulation results suggest a possibility to realize such a device.展开更多
High quality PbSe film was first fabricated by a thermal evaporation method, and then the effect of plasma sensitization on the PbSe film was systemically investigated. Typical detectivity and significant photosensiti...High quality PbSe film was first fabricated by a thermal evaporation method, and then the effect of plasma sensitization on the PbSe film was systemically investigated. Typical detectivity and significant photosensitivity are achieved in the PbSe-based photodetector, reaching maximum values of 7.6 × 10^(9)cm·Hz^(1/2)/W and 1.723 A/W, respectively. Compared with thermal annealing, plasma sensitization makes the sensitization easier and significantly improves the performance.展开更多
For the measurement of responsivity of an infrared photodetector,the most-used radiation source is a blackbody.In such a measurement system,distance between the blackbody,the photodetector and the aperture diameter ar...For the measurement of responsivity of an infrared photodetector,the most-used radiation source is a blackbody.In such a measurement system,distance between the blackbody,the photodetector and the aperture diameter are two parameters that contribute most measurement errors.In this work,we describe the configuration of our responsivity measurement system in great detail and present a method to calibrate the distance and aperture diameter.The core of this calibration method is to transfer direct measurements of these two parameters into an extraction procedure by fitting the experiment data to the calculated results.The calibration method is proved experimentally with a commercially extended InGaAs detector at a wide range of blackbody temperature,aperture diameter and distance.Then proof procedures are further extended into a detector fabricated in our laboratory and consistent results were obtained.展开更多
Infrared and terahertz waves constitute pivotal bands within the electromagnetic spectrum,distinguished by their robust penetration capabilities and non-ionizing nature.These wavebands offer the potential for achievin...Infrared and terahertz waves constitute pivotal bands within the electromagnetic spectrum,distinguished by their robust penetration capabilities and non-ionizing nature.These wavebands offer the potential for achieving high-resolution and non-destructive detection methodologies,thereby possessing considerable research significance across diverse domains including communication technologies,biomedical applications,and security screening systems.Two-dimensional materials,owing to their distinctive optoelectronic attributes,have found widespread application in photodetection endeavors.Nonetheless,their efficacy diminishes when tasked with detecting lower photon energies.Furthermore,as the landscape of device integration evolves,two-dimensional materials struggle to align with the stringent demands for device superior performance.Topological materials,with their topologically protected electronic states and non-trivial topological invariants,exhibit quantum anomalous Hall effects and ultra-high carrier mobility,providing a new approach for seeking photosensitive materials for infrared and terahertz photodetectors.This article introduces various types of topological materials and their properties,followed by an explanation of the detection mechanism and performance parameters of photodetectors.Finally,it summarizes the current research status of near-infrared to far-infrared photodetectors and terahertz photodetectors based on topological materials,discussing the challenges faced and future prospects in their development.展开更多
For non-destructive optical characterization, laser beam induced current(LBIC) microscopy has been developed into as a quantitative tool to examine individual photodiodes within a large pixel array. Two-dimensional LB...For non-destructive optical characterization, laser beam induced current(LBIC) microscopy has been developed into as a quantitative tool to examine individual photodiodes within a large pixel array. Two-dimensional LBIC microscopy, also generally called photocurrent mapping(PC mapping), can provide spatially resolved information about local electrical properties and p-n junction formation in photovoltaic infrared(including visible light) photodetectors from which it is possible to extract material and device parameters such as junction area, junction depth, diffusion length, leakage current position and minority carrier diffusion length etc. This paper presents a comprehensive review of research background, operating principle, fundamental issues, and applications of LBIC or PC mapping.展开更多
Infrared photodetectors have attracted much attention considering their wide civil and military applications.Two-dimensional(2D)materials offer new opportunities for the development of costless,high-level integration ...Infrared photodetectors have attracted much attention considering their wide civil and military applications.Two-dimensional(2D)materials offer new opportunities for the development of costless,high-level integration and high-performance infrared photodetectors.With the advent of a broad investigation of infrared photodetectors based on graphene and transition metal chalcogenides(TMDs)exhibiting unique properties in recent decades,research on the better performance of 2D-based infrared photodetectors has been extended to a larger scale,including explorations of new materials and artificial structure designs.In this review,after a brief background introduction,some major working mechanisms,including the photovoltaic effect,photoconductive effect,photogating effect,photothermoelectric effect and bolometric effect,are briefly offered.Then,the discussion mainly focuses on the recent progress of three categories of 2D materials beyond graphene and TMDs.Noble transition metal dichalcogenides,black phosphorus and arsenic black phosphorous and 2D ternary compounds are great examples of explorations of mid-wavelength or even long-wavelength 2D infrared photodetectors.Then,four types of rational structure designs,including type-II band alignments,photogating-enhanced designs,surface plasmon designs and ferroelectric-enhanced designs,are discussed to further enhance the performance via diverse mechanisms,which involve the narrower-bandgap-induced interlayer exciton transition,gate modulation by trapped carriers,surface plasmon polaritons and ferroelectric polarization in sequence.Furthermore,applications including imaging,flexible devices and on-chip integration for 2D-based infrared photodetectors are introduced.Finally,a summary of the state-of-the-art research status and personal discussion on the challenges are delivered.展开更多
Photodetectors operating in the shortwave infrared region are of great significance due to their extensive applications in both commercial and military fields.Narrowbandgap two-dimensional layered materials(2DLMs)are ...Photodetectors operating in the shortwave infrared region are of great significance due to their extensive applications in both commercial and military fields.Narrowbandgap two-dimensional layered materials(2DLMs)are considered as the promising candidates for constructing nextgeneration high-performance infrared photodetectors.Nevertheless,the performance of 2DLMs-based photodetectors can hardly satisfy the requirements of practical applications due to their weak optical absorption.In the present study,a strategy was proposed to design high-performance shortwave infrared photodetectors by integrating metalorganic frameworks(MOFs)nanoparticles with excellent optical absorption characteristics and 2DLM with high mobility.Further,this study demonstrated the practicability of this strategy in a MOF/2DLM(Ni-CAT-1/Bi_(2)Se_(3))hybrid heterojunction photodetector.Due to the transfer of photo-generated carriers from the MOF to Bi_(2)Se_(3),the MOF nanoparticles integrated on the Bi_(2)Se_(3) layer can increase the photocurrent by 2-3 orders of magnitude.The resulting photodetector presented a high responsivity of 4725 A W^(−1) and a superior detectivity of 3.5×10^(13) Jones at 1500 nm.The outstanding performance of the hybrid heterojunction arises from the synergistic function of the enhanced optical absorption and photogating effect.In addition,the proposed device construction strategy combining MOF photosensitive materials with 2DLMs shows a high potential for the future high-performance shortwave infrared photodetectors.展开更多
Low-dimensional inorganic nanostructures such as quantum dots as well as one-and two-dimensional nanostructures are widely studied and already used in high-performance infrared photodetectors.These structures feature ...Low-dimensional inorganic nanostructures such as quantum dots as well as one-and two-dimensional nanostructures are widely studied and already used in high-performance infrared photodetectors.These structures feature large surface-to-volume ratios,tunable light absorption,and electron-limiting effects.This article reviews the state-of-the-art research of low-dimensional inorganic nanostructures and their application for infrared photodetection.Thanks to nano-structuring,a narrow bandgap,hybrid systems,surface-plasmon resonance,and doping,many common semiconductors have the potential to be used for infrared detection.The basic approaches towards infrared detection are summarized.Furthermore,a selection of very important and special nanostructured materials and their remarkable infrared-detection properties are introduced(e.g.,black phosphorus,graphene-based,MoX_(2)-based,Ⅲ-Ⅶ group).Each section in this review describes the corresponding photosensitive properties in detail.The article concludes with an outlook of anticipated future developments in the field.展开更多
Palladium diselenide(PdSe2),a stable layered material with pentagonal structure,has attracted extensive interest due to its excellent electrical and optoelectronic performance.Here,we report a reliable process to synt...Palladium diselenide(PdSe2),a stable layered material with pentagonal structure,has attracted extensive interest due to its excellent electrical and optoelectronic performance.Here,we report a reliable process to synthesize PdSe2 via chemical vapor deposition(CVD)method.Through systematic regulation of temperature in the growth process,we can tune the thickness,size,nucleation density and morphology of PdSe2 nanosheets.Field-effect transistors based on PdSe2 nanosheets exhibit n-type behavior and present a high electron mobility of 105 cm^2·V^−1·s^−1.The electrical property of the devices after 6 months keeping in the air show little change,implying outstanding air-stability of PdSe2.In addition,PdSe2 near-infrared photodetector shows a photoresponsivity of 660 A·W^−1 under 914 nm laser.These performances are better than those of most CVD-grown 2D materials,making ultrathin PdSe2 a highly qualified candidate material for next-generation optoelectronic applications.展开更多
Ti_(3)C_(2) MXe ne servi ng as superior electrical con ductors prese nts more specific performa nee such as tran spar ency,con ductivity tha n gold(Au),and even could form a heterostructure with active materials of th...Ti_(3)C_(2) MXe ne servi ng as superior electrical con ductors prese nts more specific performa nee such as tran spar ency,con ductivity tha n gold(Au),and even could form a heterostructure with active materials of the functional devices.Here,a Ti_(3)C_(2) MXene-Te microplate van der Waals heterostructure based tran spare nt near-i nfrared photodetector(PD)is exploited.展开更多
Pre-strained nanomembranes with four embedded quantum wells（QWs） are rolled up into threedimensional（3D） tubular QW infrared photodetectors（QWIPs）,which are based on the QW intersubband transition（ISBT）.A reds...Pre-strained nanomembranes with four embedded quantum wells（QWs） are rolled up into threedimensional（3D） tubular QW infrared photodetectors（QWIPs）,which are based on the QW intersubband transition（ISBT）.A redshift of ～0.42 meV in photocurrent response spectra is observed and attributed to two strain contributions due to the rolling of the pre-strained nanomembranes.One is the overall strain that mainly leads to a redshift of ～0.5 meV,and the other is the strain gradient which results in a very tiny variation.The blue shift of the photocurrent response spectra with the external bias are also observed as quantum-confined Stark effect（QCSE）in the ISBT.展开更多
A complete quantum mechanical model for GaAs?AlGaAs quantum well infrared photodetectors(QWIPs) is presented here. The model consisted of four parts: (1) Starting with the description of the electromagnetic field of t...A complete quantum mechanical model for GaAs?AlGaAs quantum well infrared photodetectors(QWIPs) is presented here. The model consisted of four parts: (1) Starting with the description of the electromagnetic field of the infrared radiation in the QWIP, effective component of the vector potential <| A z |> along the QWIP growth direction ( z axis) due to the optical diffraction grating was calculated. (2) From the wave transmissions and the occupations of the electronic states, it was discussed that the dark current in the QWIP is determined by the drift diffusion current of carriers thermally excited from the ground sublevel in the quantum well to extended states above the barrier. (3) The photocurrent was investigated by the optical transition (absorption coefficient between the ground state to excited states due to the nonzero <| A z |> ). (4) By studying the inter diffusion of the Al atoms across the GaAs?AlGaAs heterointerfaces,the mobility of the drift diffusion carriers in the excited states was calculated, so the measurement results of the dark current and photocurrent spectra can be explained theoretically. With the complete quantum mechanical descriptions of (1 4), QWIP device design and optimization are possible.展开更多
Standard GaAs/AlGaAs quantum well infrared photodetectors(QWIP)have been seriously considered as atechnological choice for the 3^(rd) generation of thermal imagers in the long wave infrared band(LWIR)for some time.Alt...Standard GaAs/AlGaAs quantum well infrared photodetectors(QWIP)have been seriously considered as atechnological choice for the 3^(rd) generation of thermal imagers in the long wave infrared band(LWIR)for some time.Alternative technology like MCT(HgCdTe)was the technology choice of the 2^(nd) generation because of its high quantum efficiency.In the paper,measurements on the QWIP technology will be presented and a comparison with alternative technology will be done.展开更多
We report on a long wavelength interband cascade photodetector with type Ⅱ InAs/GaSb superlattice absorber.The device is a three-stage interband cascade structure.At 77 K,the 50%cutoff wavelength of the detector is 8...We report on a long wavelength interband cascade photodetector with type Ⅱ InAs/GaSb superlattice absorber.The device is a three-stage interband cascade structure.At 77 K,the 50%cutoff wavelength of the detector is 8.48μm and the peak photoresponse wavelength is 7.78μm.The peak responsivity is 0.93 A/W and the detectivity D*is 1.12×10^(11)cm·Hz0.5/W for 7.78μm at-0.20 V.The detector can operate up to about 260 K.At 260 K,the 50%cutoff wavelength is 11.52μm,the peak responsivity is 0.78 A/W and the D*is 5.02×10^(8)cm·Hz0.5/W for the peak wavelength of 10.39μm at-2.75 V.The dark current of the device is dominated by the diffusion current under both a small bias voltage of-0.2 V and a large one of-2.75 V for the temperature range of 120 to 260 K.展开更多
This study introduces a comprehensive theoretical framework for accurately calculating the electronic band-structure of strained long-wavelength InAs/GaSb type-Ⅱsuperlattices.Utilizing an eight-band k·p Hamilto⁃...This study introduces a comprehensive theoretical framework for accurately calculating the electronic band-structure of strained long-wavelength InAs/GaSb type-Ⅱsuperlattices.Utilizing an eight-band k·p Hamilto⁃nian in conjunction with a scattering matrix method,the model effectively incorporates quantum confinement,strain effects,and interface states.This robust and numerically stable approach achieves exceptional agreement with experimental data,offering a reliable tool for analyzing and engineering the band structure of complex multi⁃layer systems.展开更多
Infrared(IR)photodetectors(PDs)are crucial for medical imaging,optical communication,security surveillance,remote sensing,and gas identification.In this Letter,we systematically investigated a room temperature IR PD b...Infrared(IR)photodetectors(PDs)are crucial for medical imaging,optical communication,security surveillance,remote sensing,and gas identification.In this Letter,we systematically investigated a room temperature IR PD based on twodimensional b-As_(0.5)P_(0.5),a relatively unexplored component of b-As P alloys.We synthesized high-quality b-As_(0.5)P_(0.5) flakes via the chemical vapor transport(CVT)method with precisely controlled conditions.The fabricated b-As_(0.5)P_(0.5) PD exhibits excellent photoconductivity,high responsivity,and a fast response in the visible and near-infrared(Vis-NIR)band.It achieves a responsivity of~0.209 A·W^(-1) and a response time of~16.6μs under 1550 nm IR illumination.High-resolution single-pixel point optical imaging and high-speed optical communication were realized by the b-As_(0.5)P_(0.5) PDs.This study confirms that b-As_(0.5)P_(0.5) materials are highly promising for advanced IR optoelectronic applications.展开更多
An infrared detector with high responsivity based on graphene-PbSe thin film heterojunction was reported.High-quality PbSe thin film and graphene were prepared by molecular beam epitaxy and chemical vapor deposition,r...An infrared detector with high responsivity based on graphene-PbSe thin film heterojunction was reported.High-quality PbSe thin film and graphene were prepared by molecular beam epitaxy and chemical vapor deposition,respectively.The physical characteristics of PbSe thin film and graphene were performed using X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and Raman measurement.The photo transistor using PbSe thin film as a sensitizer and graphene as a channel to transport excitons exhibits peak responsivity and detectivity up to~420 A·W^(-1) and 5.9×10^(11) Jones(radiation intensity:0.75 mW·cm^(-2))at room temperature in the near-infrared(NIR)region,respectively.The high optical response is attributed to the photo-excited holes transferring from PbSe film to graphene under irradiation.Moreover,it is revealed that the responsivity of graphene-PbSe photo transistor is gate-tunable which is important in photodetectors.展开更多
基金supported by the National Key Research and Development Program of China (Grant No. 2024YFB3211701)the National Natural Science Foundation of China (Grant Nos. T2222011, 62174026, and 12274234)+1 种基金the National Key Research and Development Program of China (Grant Nos. 2023YFB3611400 and 2019YFA0308000)the Fundamental Research Funds for the Central Universities (Grant No. 242023k30027)。
文摘The weak interlayer van der Waals(vdW) interactions in two-dimensional(2D) vdW materials enable sliding ferroelectricity as an effective strategy for modulating their intrinsic properties. In this work, we systematically investigate the influence of interlayer sliding on the electronic behavior of PtSe_(2) using density functional theory(DFT) calculations. Our results demonstrate that interlayer sliding induces a pronounced photocurrent spanning the short-wavelength infrared to visible spectral ranges. Remarkably, under an applied gate voltage, the sliding ferroelectric PtSe_(2) exhibits anomalously enhanced photovoltaic performance and an ultrahigh extinction ratio.Transmission spectral analysis reveals that this phenomenon originates from band structure modifications driven by energy-level transitions. Furthermore, the observed photocurrent enhancement via sliding ferroelectricity demonstrates universality across diverse platinum-based optoelectronic devices. This study introduces a novel paradigm for tailoring the intrinsic characteristics of 2D vdW semiconductors, expanding the design space for next-generation ferroelectric materials in advanced optoelectronic applications.
基金financially supported by the National Natural Science Foundation of China (Grant No. 61991442)。
文摘Quantum well infrared photodetectors(QWIPs) based on intersubband transitions hold significant potential for high bandwidth operation. In this work, we establish a carrier transport optimization model incorporating electron injection at the emitter to investigate the carrier dynamics time and impedance spectroscopy in GaAs/AlGaAs QWIPs. Our findings provide novel evidence that the escape time of electrons is the key limiting factor for the 3-dB bandwidth of QWIPs. Moreover, to characterize the impact of carrier dynamics time and non-equilibrium space charge region on impedance, we developed an equivalent circuit model where depletion region resistance and capacitance are employed to describe non-equilibrium space charge region. Using this model, we discovered that under illumination, both net charge accumulation caused by variations in carrier dynamics times within quantum wells and changes in width of non-equilibrium space charge region exert different dominant influences on depletion region capacitance at various doping concentrations.
文摘We design and fabricate a 128 × 128 AlGaAs/GaAs quantum well infrared photodetector focal plane array （FPA）. The device is achieved by metal organic chemical vapor deposition and GaAs integrated circuit processing technology. A test structure of the photodetector with a mesa size of 300μm × 300μm is also made in order to obtain the device parameters. The measured dark current density at 77K is 1.5 × 10^-3A/cm^2 with a bias voltage of 2V. The peak of the responsivity spectrum is at 8.4μm,with a cutoff wavelength of 9μm. The blackbody detectivity is shown to be 3.95 × 10^8 （cm · Hz^1/2）/W. The final FPA is flip-chip bonded on a CMOS read-out integrated circuit. The infrared thermal images of some targets at room temperature background are successfully demonstrated at 80K operating temperature with a ratio of dead pixels of less than 1%.
文摘Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral range.Despite the fact that they already achieved notable success,the performance suffers from the thermionic emission of electrons from the quantum dots at elevated temperatures resulting in a decreasing responsivity.In order to provide an efficient carrier injection at high temperatures,quantum dot infrared photodetectors can be separated into two parts:an injection part and a detection part,so that each part can be separately optimized.In order to integrate such functionality into a device,a new class of quantum dot infrared photodetectors using quantum dot molecules will be introduced.In addition to a general discussion simulation results suggest a possibility to realize such a device.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61605207, 61704172, and 61705229)the Key Research and Development Plan of the Ministry of Science and Technology of China (Grant No. 2017YFE0131900)+1 种基金the Western Light Program of the Chinese Academy of SciencesYouth Innovation Promotion Association of Chinese Academy of Sciences (Grant No. 2018416)。
文摘High quality PbSe film was first fabricated by a thermal evaporation method, and then the effect of plasma sensitization on the PbSe film was systemically investigated. Typical detectivity and significant photosensitivity are achieved in the PbSe-based photodetector, reaching maximum values of 7.6 × 10^(9)cm·Hz^(1/2)/W and 1.723 A/W, respectively. Compared with thermal annealing, plasma sensitization makes the sensitization easier and significantly improves the performance.
基金This work was supported by the National Key Technologies R&D Program of China(No.2019YFA0705203,2019YFA070104)the National Natural Science Foundation of China(No.62004189)the State Key Laboratory of Special Rare Metal Materials,Northwest Rare Metal Materials Research Institute(No.SKL2023K00X).
文摘For the measurement of responsivity of an infrared photodetector,the most-used radiation source is a blackbody.In such a measurement system,distance between the blackbody,the photodetector and the aperture diameter are two parameters that contribute most measurement errors.In this work,we describe the configuration of our responsivity measurement system in great detail and present a method to calibrate the distance and aperture diameter.The core of this calibration method is to transfer direct measurements of these two parameters into an extraction procedure by fitting the experiment data to the calculated results.The calibration method is proved experimentally with a commercially extended InGaAs detector at a wide range of blackbody temperature,aperture diameter and distance.Then proof procedures are further extended into a detector fabricated in our laboratory and consistent results were obtained.
基金supported by the National Key R&D Program of China(Grant No.2024YFA1211300)Outstanding Youth Foundation of NSFC(Grant No.62322515)+5 种基金Municipal Science and Technology Major Project(Grant No.2019SHZDZX01)Shanghai Natural Science Foundation Project(Grant No.24ZR1493100)International Partnership Program of Chinese Academy of Sciences(Grant No.112GJHZ2024039FN)the support from Analytical Instrumentation Center(#SPST-AIC10112914)Soft Matter Nanofab(#SPST-SMN180827)Quantum Device Lab,Shanghai Tech University。
文摘Infrared and terahertz waves constitute pivotal bands within the electromagnetic spectrum,distinguished by their robust penetration capabilities and non-ionizing nature.These wavebands offer the potential for achieving high-resolution and non-destructive detection methodologies,thereby possessing considerable research significance across diverse domains including communication technologies,biomedical applications,and security screening systems.Two-dimensional materials,owing to their distinctive optoelectronic attributes,have found widespread application in photodetection endeavors.Nonetheless,their efficacy diminishes when tasked with detecting lower photon energies.Furthermore,as the landscape of device integration evolves,two-dimensional materials struggle to align with the stringent demands for device superior performance.Topological materials,with their topologically protected electronic states and non-trivial topological invariants,exhibit quantum anomalous Hall effects and ultra-high carrier mobility,providing a new approach for seeking photosensitive materials for infrared and terahertz photodetectors.This article introduces various types of topological materials and their properties,followed by an explanation of the detection mechanism and performance parameters of photodetectors.Finally,it summarizes the current research status of near-infrared to far-infrared photodetectors and terahertz photodetectors based on topological materials,discussing the challenges faced and future prospects in their development.
基金supported by the State Key Program for Basic Research of China(Grant No.2014CB921600)the National Natural Science Foundation of China(Grant Nos.11322441 and 11274331)the Fund of Shanghai Science and Technology Foundation(Grant No.14JC1406400)
文摘For non-destructive optical characterization, laser beam induced current(LBIC) microscopy has been developed into as a quantitative tool to examine individual photodiodes within a large pixel array. Two-dimensional LBIC microscopy, also generally called photocurrent mapping(PC mapping), can provide spatially resolved information about local electrical properties and p-n junction formation in photovoltaic infrared(including visible light) photodetectors from which it is possible to extract material and device parameters such as junction area, junction depth, diffusion length, leakage current position and minority carrier diffusion length etc. This paper presents a comprehensive review of research background, operating principle, fundamental issues, and applications of LBIC or PC mapping.
基金the National Natural Science Foundation of China(No.52072308)the Open Project of Basic Research of Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing(No.AMGM2022F02)the Fundamental Research Funds for the Central Universities(Nos.3102021MS0404 and 3102019JC001).
文摘Infrared photodetectors have attracted much attention considering their wide civil and military applications.Two-dimensional(2D)materials offer new opportunities for the development of costless,high-level integration and high-performance infrared photodetectors.With the advent of a broad investigation of infrared photodetectors based on graphene and transition metal chalcogenides(TMDs)exhibiting unique properties in recent decades,research on the better performance of 2D-based infrared photodetectors has been extended to a larger scale,including explorations of new materials and artificial structure designs.In this review,after a brief background introduction,some major working mechanisms,including the photovoltaic effect,photoconductive effect,photogating effect,photothermoelectric effect and bolometric effect,are briefly offered.Then,the discussion mainly focuses on the recent progress of three categories of 2D materials beyond graphene and TMDs.Noble transition metal dichalcogenides,black phosphorus and arsenic black phosphorous and 2D ternary compounds are great examples of explorations of mid-wavelength or even long-wavelength 2D infrared photodetectors.Then,four types of rational structure designs,including type-II band alignments,photogating-enhanced designs,surface plasmon designs and ferroelectric-enhanced designs,are discussed to further enhance the performance via diverse mechanisms,which involve the narrower-bandgap-induced interlayer exciton transition,gate modulation by trapped carriers,surface plasmon polaritons and ferroelectric polarization in sequence.Furthermore,applications including imaging,flexible devices and on-chip integration for 2D-based infrared photodetectors are introduced.Finally,a summary of the state-of-the-art research status and personal discussion on the challenges are delivered.
基金supported by the National Natural Science Foundation of China(21825103 and 51727809)the Natural Science Foundation of Hubei Province(2019CFA002)+1 种基金the Fundamental Research Funds for the Central Universities(2019kfyXMBZ018)China Postdoctoral Science Foundation(2021M691108)。
文摘Photodetectors operating in the shortwave infrared region are of great significance due to their extensive applications in both commercial and military fields.Narrowbandgap two-dimensional layered materials(2DLMs)are considered as the promising candidates for constructing nextgeneration high-performance infrared photodetectors.Nevertheless,the performance of 2DLMs-based photodetectors can hardly satisfy the requirements of practical applications due to their weak optical absorption.In the present study,a strategy was proposed to design high-performance shortwave infrared photodetectors by integrating metalorganic frameworks(MOFs)nanoparticles with excellent optical absorption characteristics and 2DLM with high mobility.Further,this study demonstrated the practicability of this strategy in a MOF/2DLM(Ni-CAT-1/Bi_(2)Se_(3))hybrid heterojunction photodetector.Due to the transfer of photo-generated carriers from the MOF to Bi_(2)Se_(3),the MOF nanoparticles integrated on the Bi_(2)Se_(3) layer can increase the photocurrent by 2-3 orders of magnitude.The resulting photodetector presented a high responsivity of 4725 A W^(−1) and a superior detectivity of 3.5×10^(13) Jones at 1500 nm.The outstanding performance of the hybrid heterojunction arises from the synergistic function of the enhanced optical absorption and photogating effect.In addition,the proposed device construction strategy combining MOF photosensitive materials with 2DLMs shows a high potential for the future high-performance shortwave infrared photodetectors.
基金supported by the National Natural Science Foundation of China(Nos.21561031,51972055,and 21701135)the Shenzhen Science and Technology Research Project(No.JCYJ20180508152903208)+1 种基金the Shenzhen Pengcheng Scholar Program,the Guangdong Basic and Applied Basic Research Foundation(No.2020A1515010258)Shenzhen Bay Laboratory Open Fund(No.SZBL2020090501002).
文摘Low-dimensional inorganic nanostructures such as quantum dots as well as one-and two-dimensional nanostructures are widely studied and already used in high-performance infrared photodetectors.These structures feature large surface-to-volume ratios,tunable light absorption,and electron-limiting effects.This article reviews the state-of-the-art research of low-dimensional inorganic nanostructures and their application for infrared photodetection.Thanks to nano-structuring,a narrow bandgap,hybrid systems,surface-plasmon resonance,and doping,many common semiconductors have the potential to be used for infrared detection.The basic approaches towards infrared detection are summarized.Furthermore,a selection of very important and special nanostructured materials and their remarkable infrared-detection properties are introduced(e.g.,black phosphorus,graphene-based,MoX_(2)-based,Ⅲ-Ⅶ group).Each section in this review describes the corresponding photosensitive properties in detail.The article concludes with an outlook of anticipated future developments in the field.
基金We acknowledge the support from National Natural Science Foundation of China(Nos.61804050,51991340,51991343,and 51872086)the Fundamental Research Funds of the Central Universities(Nos.531107051078 and 531107051055)+2 种基金the Double First-Class Initiative of Hunan University(No.531109100004)the Hunan Key Laboratory of Two-Dimensional Materials(No.2018TP1010)the Strategic Priority Research Program of Chinese Academy of Science,Grant(No.XDB30000000).
文摘Palladium diselenide(PdSe2),a stable layered material with pentagonal structure,has attracted extensive interest due to its excellent electrical and optoelectronic performance.Here,we report a reliable process to synthesize PdSe2 via chemical vapor deposition(CVD)method.Through systematic regulation of temperature in the growth process,we can tune the thickness,size,nucleation density and morphology of PdSe2 nanosheets.Field-effect transistors based on PdSe2 nanosheets exhibit n-type behavior and present a high electron mobility of 105 cm^2·V^−1·s^−1.The electrical property of the devices after 6 months keeping in the air show little change,implying outstanding air-stability of PdSe2.In addition,PdSe2 near-infrared photodetector shows a photoresponsivity of 660 A·W^−1 under 914 nm laser.These performances are better than those of most CVD-grown 2D materials,making ultrathin PdSe2 a highly qualified candidate material for next-generation optoelectronic applications.
基金This work was supported by the National Natural Science Foundation of China(No.61888102).
文摘Ti_(3)C_(2) MXe ne servi ng as superior electrical con ductors prese nts more specific performa nee such as tran spar ency,con ductivity tha n gold(Au),and even could form a heterostructure with active materials of the functional devices.Here,a Ti_(3)C_(2) MXene-Te microplate van der Waals heterostructure based tran spare nt near-i nfrared photodetector(PD)is exploited.
基金Project supported by the Natural Science Foundation of China(Nos.51322201,61575213)the Shanghai Municipal Science and Technology Commission(No.14JC 1400200)
文摘Pre-strained nanomembranes with four embedded quantum wells（QWs） are rolled up into threedimensional（3D） tubular QW infrared photodetectors（QWIPs）,which are based on the QW intersubband transition（ISBT）.A redshift of ～0.42 meV in photocurrent response spectra is observed and attributed to two strain contributions due to the rolling of the pre-strained nanomembranes.One is the overall strain that mainly leads to a redshift of ～0.5 meV,and the other is the strain gradient which results in a very tiny variation.The blue shift of the photocurrent response spectra with the external bias are also observed as quantum-confined Stark effect（QCSE）in the ISBT.
文摘A complete quantum mechanical model for GaAs?AlGaAs quantum well infrared photodetectors(QWIPs) is presented here. The model consisted of four parts: (1) Starting with the description of the electromagnetic field of the infrared radiation in the QWIP, effective component of the vector potential <| A z |> along the QWIP growth direction ( z axis) due to the optical diffraction grating was calculated. (2) From the wave transmissions and the occupations of the electronic states, it was discussed that the dark current in the QWIP is determined by the drift diffusion current of carriers thermally excited from the ground sublevel in the quantum well to extended states above the barrier. (3) The photocurrent was investigated by the optical transition (absorption coefficient between the ground state to excited states due to the nonzero <| A z |> ). (4) By studying the inter diffusion of the Al atoms across the GaAs?AlGaAs heterointerfaces,the mobility of the drift diffusion carriers in the excited states was calculated, so the measurement results of the dark current and photocurrent spectra can be explained theoretically. With the complete quantum mechanical descriptions of (1 4), QWIP device design and optimization are possible.
文摘Standard GaAs/AlGaAs quantum well infrared photodetectors(QWIP)have been seriously considered as atechnological choice for the 3^(rd) generation of thermal imagers in the long wave infrared band(LWIR)for some time.Alternative technology like MCT(HgCdTe)was the technology choice of the 2^(nd) generation because of its high quantum efficiency.In the paper,measurements on the QWIP technology will be presented and a comparison with alternative technology will be done.
基金supported in part by China’s NSF Program 61874103
文摘We report on a long wavelength interband cascade photodetector with type Ⅱ InAs/GaSb superlattice absorber.The device is a three-stage interband cascade structure.At 77 K,the 50%cutoff wavelength of the detector is 8.48μm and the peak photoresponse wavelength is 7.78μm.The peak responsivity is 0.93 A/W and the detectivity D*is 1.12×10^(11)cm·Hz0.5/W for 7.78μm at-0.20 V.The detector can operate up to about 260 K.At 260 K,the 50%cutoff wavelength is 11.52μm,the peak responsivity is 0.78 A/W and the D*is 5.02×10^(8)cm·Hz0.5/W for the peak wavelength of 10.39μm at-2.75 V.The dark current of the device is dominated by the diffusion current under both a small bias voltage of-0.2 V and a large one of-2.75 V for the temperature range of 120 to 260 K.
文摘This study introduces a comprehensive theoretical framework for accurately calculating the electronic band-structure of strained long-wavelength InAs/GaSb type-Ⅱsuperlattices.Utilizing an eight-band k·p Hamilto⁃nian in conjunction with a scattering matrix method,the model effectively incorporates quantum confinement,strain effects,and interface states.This robust and numerically stable approach achieves exceptional agreement with experimental data,offering a reliable tool for analyzing and engineering the band structure of complex multi⁃layer systems.
基金supported by the National Natural Science Foundation of China(No.62105018)。
文摘Infrared(IR)photodetectors(PDs)are crucial for medical imaging,optical communication,security surveillance,remote sensing,and gas identification.In this Letter,we systematically investigated a room temperature IR PD based on twodimensional b-As_(0.5)P_(0.5),a relatively unexplored component of b-As P alloys.We synthesized high-quality b-As_(0.5)P_(0.5) flakes via the chemical vapor transport(CVT)method with precisely controlled conditions.The fabricated b-As_(0.5)P_(0.5) PD exhibits excellent photoconductivity,high responsivity,and a fast response in the visible and near-infrared(Vis-NIR)band.It achieves a responsivity of~0.209 A·W^(-1) and a response time of~16.6μs under 1550 nm IR illumination.High-resolution single-pixel point optical imaging and high-speed optical communication were realized by the b-As_(0.5)P_(0.5) PDs.This study confirms that b-As_(0.5)P_(0.5) materials are highly promising for advanced IR optoelectronic applications.
基金financially supported by the National Natural Science Foundation of China(No.51572043)。
文摘An infrared detector with high responsivity based on graphene-PbSe thin film heterojunction was reported.High-quality PbSe thin film and graphene were prepared by molecular beam epitaxy and chemical vapor deposition,respectively.The physical characteristics of PbSe thin film and graphene were performed using X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and Raman measurement.The photo transistor using PbSe thin film as a sensitizer and graphene as a channel to transport excitons exhibits peak responsivity and detectivity up to~420 A·W^(-1) and 5.9×10^(11) Jones(radiation intensity:0.75 mW·cm^(-2))at room temperature in the near-infrared(NIR)region,respectively.The high optical response is attributed to the photo-excited holes transferring from PbSe film to graphene under irradiation.Moreover,it is revealed that the responsivity of graphene-PbSe photo transistor is gate-tunable which is important in photodetectors.
