This paper presents a review of the position-sensitive detector(PSD) sensor, covering different types of PSD and recent works related to this field. Furthermore, it explains the theoretical concepts and provides infor...This paper presents a review of the position-sensitive detector(PSD) sensor, covering different types of PSD and recent works related to this field. Furthermore, it explains the theoretical concepts and provides information about its structure and principles of operation. Moreover, it includes the main information about the available commercial PSDs from different companies, along with a comparison between the common modules. The PSD features include high position resolution, fast response, and a wide dynamic range. These features make it suitable for various fields and applications, such as imaging, spectrometry, spectroscopy and others.展开更多
Ultraviolet position-sensitive detectors(PSDs)are expected to undergo harsh environments,such as high temperatures,for a wide variety of applications in military,civilian,and aerospace.However,no report on relevant PS...Ultraviolet position-sensitive detectors(PSDs)are expected to undergo harsh environments,such as high temperatures,for a wide variety of applications in military,civilian,and aerospace.However,no report on relevant PSDs operating at high temperatures can be found up to now.Herein,we design a new 2D/3D graphitic carbon nitride(g-C_(3)N_(4))/gallium nitride(GaN)hybrid heterojunction to construct the ultraviolet high-temperature-resistant PSD.The g-C_(3)N_(4)/GaN PSD exhibits a high position sensitivity of 355 mV mm^(-1),a rise/fall response time of 1.7/2.3 ms,and a nonlinearity of 0.5%at room temperature.The ultralow formation energy of-0.917 eV atom^(-1)has been obtained via the thermodynamic phase stability calculations,which endows g-C_(3)N_(4)with robust stability against heat.By merits of the strong built-in electric field of the 2D/3D hybrid heterojunction and robust thermo-stability of g-C_(3)N_(4),the g-C_(3)N_(4)/GaN PSD delivers an excellent position sensitivity and angle detection nonlinearity of 315 mV mm^(-1)and 1.4%,respectively,with high repeatability at a high temperature up to 700 K,outperforming most of the other counterparts and even commercial silicon-based devices.This work unveils the high-temperature PSD,and pioneers a new path to constructing g-C_(3)N_(4)-based harsh-environment-tolerant optoelectronic devices.展开更多
Si-based optical position-sensitive detectors(PSDs)have stimulated the interest of researchers due to their wide range of practical applications.However,due to the rigidity and fragility of Si crystals,the application...Si-based optical position-sensitive detectors(PSDs)have stimulated the interest of researchers due to their wide range of practical applications.However,due to the rigidity and fragility of Si crystals,the applications of flexible PSDs have been limited.Therefore,we presented a flexible broadband PSD based on a WS_(2)/Si heterostructure for the first time.A scalable sputtering method was used to deposit WS_(2)thin films onto the etched ultrathin crystalline Si surface.The fabricated flexible PSD device has a broad spectral response in the wavelength range of 450-1350 nm,with a high position sensitivity of~539.8 mV·mm^(−1)and a fast response of 2.3μs,thanks to the strong light absorption,the built-in electrical field at the WS_(2)/Si interface,and facilitated transport.Furthermore,mechanical-bending tests revealed that after 200 mechanical-bending cycles,the WS_(2)/Si PSDs have excellent mechanical flexibility,stability,and durability,demonstrating the great potential in wearable PSDs with competitive performance.展开更多
Two-dimensional(2D)materials have attracted great attention in optoelectronics because of their unique structure,optical and electrical properties.Designing high-performance photodetectors and implementing their appli...Two-dimensional(2D)materials have attracted great attention in optoelectronics because of their unique structure,optical and electrical properties.Designing high-performance photodetectors and implementing their applications are eager to promote the development of 2D materials.Position-sensitive detector(PSD)is an optical inspection device for the precise measurements of position,distance,angle,and other relevant physical variables.It is a widely used component in the fields of tracking,aerospace,nanorobotics,and so forth.Essentially,PSD is also a photodetector based on the lateral photovoltaic effect(LPE).This article reviews recent progress in high-performance PSD based on 2D materials.The high-sensitive photodetectors and LPE involved in 2D photodetectors are firstly discussed.Then,we introduce the research progress of PSD based on 2D materials and analyze the carrier dynamics in different device structures.Finally,we summarize the functionalities and applications of PSD based on 2D materials,and highlight the challenges and opportunities in this research area.展开更多
Motion tracking has attracted great attention in the fields of real-time tracking,nanorobotics,and targeted therapy.For achieving more accurate motion tracking,the highly sensitive position-sensitive detector(PSD)is d...Motion tracking has attracted great attention in the fields of real-time tracking,nanorobotics,and targeted therapy.For achieving more accurate motion tracking,the highly sensitive position-sensitive detector(PSD)is desirable.Here,we demonstrate a meliorated PSD based on graphene-Si heterojunction for motion tracking.The position sensitivity of PSD was improved by employing surface engineering of graphene.Through modulating the transport property of graphene,nearly 20-fold increase of sensitivity was achieved under weak light,and at the same time,the detection limit power was reduced to^2 nW.A motion tracking system was developed based on the improved PSD,and human arm swing was tracked,which demonstrated high sensitivity and real-time tracking capabilities of the PSD.In addition,the PSD can support up to^10 kHz high-frequency tracking.This work provides a new strategy for improving the performance of PSD,and promotes the development of two-dimensional materials in novel optoelectronic devices.展开更多
Monoclinic Ga2O3(β-Ga2O3)is a promising material for achieving solar-blind photodetection because of its unique characteristics,including its high breakdown electric field,radiation hardness,thermal and chemical stab...Monoclinic Ga2O3(β-Ga2O3)is a promising material for achieving solar-blind photodetection because of its unique characteristics,including its high breakdown electric field,radiation hardness,thermal and chemical stabilities,and intrinsic visible/solar-blind properties.Until now,several studies have investigated the development of high-performanceβ-Ga2O3 solar-blind photodetectors.However,these photodetectors can only detect the light intensity but not the light position.In this work,fourquadrant position-sensitive detectors(4Q-PSDs)were developed and demonstrated based onβ-Ga2O3.4Q-PSDs,comprising four identical metal-semiconductor-metal-structured photodetector components,demonstrate high uniformity,large signal-tonoise ratio,good ultraviolet/visible rejection ratio,and fast response/recovery time.Subsequently,the position of the illumination beam can be determined by analyzing the output signals of the four photodetector components.This work may indicate the promising application potential of the Ga2O3-based photodetectors in the fields of positioning,aligning,and monitoring the solarblind beams.展开更多
As a typical two-dimensional material,graphitic carbon nitride(g-CN)has attracted great interest because of its distinctive electronic,optical,and catalytic properties.However,the absence of a feasible route toward la...As a typical two-dimensional material,graphitic carbon nitride(g-CN)has attracted great interest because of its distinctive electronic,optical,and catalytic properties.However,the absence of a feasible route toward large-area and high-quality films hinders its development in optoelectronics.Herein,high-quality g-CN films have been grown on Si substrate via a vapor-phase transport-assisted condensation method.The g-CN/Si heterojunction shows an obvious response to ultraviolet–visible-near infrared photons with a responsivity of 133 A·W−1,which is two orders of magnitude higher than the best value ever reported for g-CN photodetectors.A position-sensitive detector(PSD)has been developed using the lateral photovoltaic effect of the g-CN/Si heterojunction.The PSD shows a wide response spectrum ranging from 300 to 1,100 nm,and a position sensitivity and rise/decay time of 395 mV·mm−1 and 3.1/50μs,respectively.Moreover,the application of the g-CN/Si heterojunction photodetector in trajectory tracking and acoustic detection has been realized for the first time.This work unveils the potential of g-CN for large-area photodetectors,and prospects for their applications in trajectory tracking and acoustic detection.展开更多
A foil–microchannel plate(MCP)detector,which uses electrostatic lenses and possesses both good position and timing resolutions,has been designed and simulated for beam diagnostics and mass measurements at the next-ge...A foil–microchannel plate(MCP)detector,which uses electrostatic lenses and possesses both good position and timing resolutions,has been designed and simulated for beam diagnostics and mass measurements at the next-generation heavy-ion-beam facility HIAF in China.Characterized by low energy loss and good performances of timing and position measurements,it would be located at focal planes in fragment separator HFRS for position monitoring,beam turning,Bq measurement,and trajectory reconstruction.Moreover,it will benefit the building-up of a magnetic-rigidity–energy-loss–time-offlight(BqDETOF)method at HFRS for high-precision in-flight particle identification of radioactive isotope beams on an event-by-event basis.Most importantly,the detector can be utilized for in-ring TOF and position measurements,beam-line TOF measurements at two achromatic foci,and position measurements at a dispersive focus of HFRS,thus making it possible to use two complementary mass measurement methods[isochronous mass spectrometry at the storage ring SRing and magnetic-rigidity–time-of-flight(BqTOF)at the beam-line HFRS]in one single experimental run.展开更多
A Compton camera prototype has been developed using a pixelated CZT detector with 4-by-4 pixels.Signals of the detector are read out by a VASTAT ASIC that is controlled by a self-developed DAQ board. The DAQ software ...A Compton camera prototype has been developed using a pixelated CZT detector with 4-by-4 pixels.Signals of the detector are read out by a VASTAT ASIC that is controlled by a self-developed DAQ board. The DAQ software is developed using LabVIEW, and the offline Compton imaging codes are written in C++. The prototype has been successfully calibrated, and its capabilities for source detection, spectroscopy, and Compton imaging have been demonstrated using a Cs-137 source.The angular resolution of the 662 keV line is 36° FWHM for the simple back-projection method and 9.6° FWHM for the MLEM reconstruction method. The system is ready to be extended to 11-by-11 pixels in the future, and a better imaging quality can be expected due to the better relative position resolution.展开更多
X-ray detectors show potential applications in medical imaging,materials science,and nuclear energy.To achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorpho...X-ray detectors show potential applications in medical imaging,materials science,and nuclear energy.To achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorphous selenium,cadmium telluride zinc,and perovskites,have been utilized in direct conversion X-ray detectors.However,these semiconductor materials are susceptible to temperature-induced performance degradation,crystallization,delamination,uneven lattice growth,radiation damage,and high dark current.This study explores a new approach by coupling an FC40 electronic fluorinated liquid with a specialized high-resolution and high-readout-speed complementary metal-oxide-semiconductor(CMOS)pixel array,specifically the Topmetal II−chip,to fabricate a direct conversion X-ray detector.The fluorinated liquid FC40(molecular formula:C_(21)F_(48)N_(2))is an electronic medium that is minimally affected by temperature and displays no issues with uniform conductivity.It exhibits a low dark current and minimal radiation damage and enables customizable thickness in X-ray absorption.This addresses the limitations inherent in conventional semiconductor-based detectors.In this study,simple X-ray detector imaging tests were conducted,demonstrating the excellent coupling capability between FC40 electronic fluorinated liquid and CMOS chips by the X-ray detector.A spatial resolution of 4.0 lp/mm was measured using a striped line par card,and a relatively clear image of a cockroach was displayed in the digital radiography imaging results.Preliminary test results indicated the feasibility of fabricating an X-ray detector by combining FC40 electronic fluorinated liquid and CMOS chips.Owing to the absence of issues related to chip-material coupling,a high spatial resolution could be achieved by reducing the chip pixel size.This method presents a new avenue for studies on novel liquid-based direct conversion X-ray detectors.展开更多
The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process th...The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance.展开更多
To detect space gravitational waves in the extremely low-frequency band,the telescope and optic-al platform require high stability and reliability.However,the cantilevered design presents challenges,espe-cially in the...To detect space gravitational waves in the extremely low-frequency band,the telescope and optic-al platform require high stability and reliability.However,the cantilevered design presents challenges,espe-cially in the glass-metal hetero-bonding process.This study focuses on the analysis and experimental re-search of the bonding layer in the integrated structure.By optimizing the structural configuration and select-ing suitable bonding processes,the reliability of the telescope system is enhanced.The research indicates that using J-133 adhesive achieves the best performance,with a bonding layer thickness of 0.30 mm and a metal substrate surface roughness of Ra 0.8.These findings significantly enhance the reliability of the optical sys-tem while minimizing potential risks.展开更多
The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled h...The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled hyperonantihyperon pairs to be produced at Super Tau-Charm Facility(STCF),the CP asymmetry of hyperon is expected to be tested with a statistical sensitivity of 10^(−4) or even better.To cope with the statistical precision,the systematic effects from various aspects are critical and need to be studied in detail.In this paper,the sensitivity effects on the CP violation parameters associated with the detector resolution,including those of the position and momentum,are studied and discussed in detail.The results provide valuable guidance for the design of STCF detector.展开更多
For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchma...For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchmark construction.This paper proposes an architecture for detecting detector flatness based on channel spectral dispersion.By measuring the dispersion fringes for coplanar adjustment,the final adjustment residual is improved to better than 300 nm.This result validates the feasibility of the proposed technology and provides significant technical support for the development of next-generation large-aperture sky survey equipment.展开更多
Radiation doses to patients in diagnostics and interventional radiology need to be optimized to comply with the principles of radiation protection in medical practice. This involves using specific detectors with respe...Radiation doses to patients in diagnostics and interventional radiology need to be optimized to comply with the principles of radiation protection in medical practice. This involves using specific detectors with respective diagnostic beams to carry out quality control/quality assurance tests needed to optimize patient doses in the hospital. Semiconductor detectors are used in dosimetry to verify the equipment performance and dose to patients. This work aims to assess the performance, energy dependence, and response of five commercially available semiconductor detectors in RQR, RQR-M, RQA, and RQT at Secondary Standard Dosimetry for clinical applications. The diagnostic beams were generated using Exradin A4 reference ion chamber and PTW electrometer. The ambient temperature and pressure were noted for KTP correction. The detectors designed for RQR showed good performance in RQT beams and vice versa. The detectors designed for RQR-M displayed high energy dependency in other diagnostic beams. The type of diagnostic beam quality determines the response of semiconductor detectors. Therefore, a detector should be calibrated according to the beam qualities to be measured.展开更多
The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.How...The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.However,conventional polarization detection systems are often bulky and complex,limiting their poten⁃tial for broader applications.To address the challenges of miniaturization,integrated polarization detectors have been extensively explored in recent years,achieving significant advancements in performance and functionality.In this review,we focus mainly on integrated polarization detectors with innovative features,including infinitely high polarization discrimination,ultrahigh sensitivity to polarization state change,full Stokes parameters measure⁃ment,and simultaneous perception of polarization and other key properties of light.Lastly,we discuss the oppor⁃tunities and challenges for the future development of integrated polarization photodetectors.展开更多
Position-sensitive neutron detectors play an important role in neutron scattering studies. Detectors based on ~6LiF/ZnS(Ag) scintillator and wave-shifting fiber have the advantages of high neutron detection efficiency...Position-sensitive neutron detectors play an important role in neutron scattering studies. Detectors based on ~6LiF/ZnS(Ag) scintillator and wave-shifting fiber have the advantages of high neutron detection efficiency, high position resolution,and large-area splicing, and can well meet the requirement of large area neutron detection for neutron diffractometers. An engineering detector prototype based on a ~6LiF/ZnS(Ag) scintillation screen and SiPM array readout was fabricated for the General Purpose Powder Diffractometer of China Spallation Neutron Source(CSNS). The detector has an active area of 196 mm × 444 mm, with a pixel size of 4 mm × 4 mm. The key performances of the detector prototype were tested at the BL20 neutron beam line of CSNS. The test results show that the neutron detection efficiency of the detector was 32% and 42% at wavelengths of 1.4 ? and 2.8 ?, respectively. An interpolated neutron detection efficiency of 40.2% at a wavelength of 2 ? was obtained. The tested neutron efficiency non-uniformity of the detector was 10.2%, which is less than one-half that of the current general purpose powder diffractometer scintillator neutron detectors at CSNS. This work achieves, for the first time, an efficiency uniformity of < 11% in large-area mosaic neutron detectors, alongside significant advancements in electromagnetic interference immunity and cost-effectiveness.展开更多
The measurement of low-level radioactivity using high-purity germanium(HPGe)detectors is important in applications such as environmental background radiation,material screening,and rare decays.The dead layers,dead zon...The measurement of low-level radioactivity using high-purity germanium(HPGe)detectors is important in applications such as environmental background radiation,material screening,and rare decays.The dead layers,dead zones,aluminum shell thickness,and diameter of Ge crystals are the most influential factors affecting the performance of HPGe detectors;hence,precise modeling of the physical conditions of the detectors is highly desirable.In this study,the GEANT4 simulation framework with an optimized detector geometry adequately replicated the experimentally recorded spectrum.These detector simulations explored the idea of realizing a dead zone(an inactive volume)at the backend of an n-type coaxial Gecrystal.Using multigamma sources,the effect of true coincidence summing(TCS)on the full energy peak(FEP)efficiency calibration of an HPGe detector was investigated as a function of sample-to-detector distance.Good agreements between the simulated and experimental efficiencies as well as the simulated and analytically calculated summing coincidence correction coefficients were achieved.At a short distance between the source and detector,calculating the correction factors for a strong source posed challenges owing to significant deadtime and pile-up effects of the detection system.The described methodology can efficiently determine summing peak probabilities at short sample-to-detector distances.展开更多
A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nu...A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nuclei.The digital data acquisition system enables precise synchronization and processing of complex signals from various detectors,such as plastic scintillators,silicon detectors,and germaniumγdetectors.The system's performance was evaluated using theβdecay of^(32)Ar and its neighboring nuclei,produced via projectile fragmentation at the first Radioactive Ion Beam Line in Lanzhou(RIBLL1).Key measurements,including the half-life,charged-particle spectrum,andγ-ray spectrum,were obtained and compared with previous results for validation.Using the implantation–decay method,the isotopes of interest were implanted into two doublesided silicon strip detectors,where their subsequent decays were measured and correlated with preceding implantations using both position and time information.This detection system has potential for further applications,including the study ofβ-delayed charged-particle decay and direct proton emissions from even more exotic proton-rich nuclei.展开更多
文摘This paper presents a review of the position-sensitive detector(PSD) sensor, covering different types of PSD and recent works related to this field. Furthermore, it explains the theoretical concepts and provides information about its structure and principles of operation. Moreover, it includes the main information about the available commercial PSDs from different companies, along with a comparison between the common modules. The PSD features include high position resolution, fast response, and a wide dynamic range. These features make it suitable for various fields and applications, such as imaging, spectrometry, spectroscopy and others.
基金financially supported by the National Natural Science Foundation of China(No.61804136,U1804155,11974317,62027816,12074348,and U2004168)Henan Science Fund for Distinguished Young Scholars(No.212300410020)+2 种基金Natural Science Foundation of Henan Province(No.212300410020 and 212300410078)Key Project of Henan Higher Education(No.21A140001)the Zhengzhou University Physics Discipline Improvement Program and China Postdoctoral Science Foundation(No.2018M630829 and 2019 T120630)
文摘Ultraviolet position-sensitive detectors(PSDs)are expected to undergo harsh environments,such as high temperatures,for a wide variety of applications in military,civilian,and aerospace.However,no report on relevant PSDs operating at high temperatures can be found up to now.Herein,we design a new 2D/3D graphitic carbon nitride(g-C_(3)N_(4))/gallium nitride(GaN)hybrid heterojunction to construct the ultraviolet high-temperature-resistant PSD.The g-C_(3)N_(4)/GaN PSD exhibits a high position sensitivity of 355 mV mm^(-1),a rise/fall response time of 1.7/2.3 ms,and a nonlinearity of 0.5%at room temperature.The ultralow formation energy of-0.917 eV atom^(-1)has been obtained via the thermodynamic phase stability calculations,which endows g-C_(3)N_(4)with robust stability against heat.By merits of the strong built-in electric field of the 2D/3D hybrid heterojunction and robust thermo-stability of g-C_(3)N_(4),the g-C_(3)N_(4)/GaN PSD delivers an excellent position sensitivity and angle detection nonlinearity of 315 mV mm^(-1)and 1.4%,respectively,with high repeatability at a high temperature up to 700 K,outperforming most of the other counterparts and even commercial silicon-based devices.This work unveils the high-temperature PSD,and pioneers a new path to constructing g-C_(3)N_(4)-based harsh-environment-tolerant optoelectronic devices.
基金supported by the National Natural Science Foundation of China(No.51972341)the Shandong Natural Science Foundation,China(No.ZR2020MA069).
文摘Si-based optical position-sensitive detectors(PSDs)have stimulated the interest of researchers due to their wide range of practical applications.However,due to the rigidity and fragility of Si crystals,the applications of flexible PSDs have been limited.Therefore,we presented a flexible broadband PSD based on a WS_(2)/Si heterostructure for the first time.A scalable sputtering method was used to deposit WS_(2)thin films onto the etched ultrathin crystalline Si surface.The fabricated flexible PSD device has a broad spectral response in the wavelength range of 450-1350 nm,with a high position sensitivity of~539.8 mV·mm^(−1)and a fast response of 2.3μs,thanks to the strong light absorption,the built-in electrical field at the WS_(2)/Si interface,and facilitated transport.Furthermore,mechanical-bending tests revealed that after 200 mechanical-bending cycles,the WS_(2)/Si PSDs have excellent mechanical flexibility,stability,and durability,demonstrating the great potential in wearable PSDs with competitive performance.
基金the National Natural Science Foundation of China(Nos.61927808,61774034,and 11704068)the National Key Research and Development Program of China(No.2017YFA0205700)China Postdoctoral Science Foundation(No.2018M632197).
文摘Two-dimensional(2D)materials have attracted great attention in optoelectronics because of their unique structure,optical and electrical properties.Designing high-performance photodetectors and implementing their applications are eager to promote the development of 2D materials.Position-sensitive detector(PSD)is an optical inspection device for the precise measurements of position,distance,angle,and other relevant physical variables.It is a widely used component in the fields of tracking,aerospace,nanorobotics,and so forth.Essentially,PSD is also a photodetector based on the lateral photovoltaic effect(LPE).This article reviews recent progress in high-performance PSD based on 2D materials.The high-sensitive photodetectors and LPE involved in 2D photodetectors are firstly discussed.Then,we introduce the research progress of PSD based on 2D materials and analyze the carrier dynamics in different device structures.Finally,we summarize the functionalities and applications of PSD based on 2D materials,and highlight the challenges and opportunities in this research area.
基金China Postdoctoral Science Foundation,Grant/Award Number:2018M632197Funding of Natural Science Research Projects in Colleges and Universities of Jiangsu Province,Grant/Award Number:18KJD140003+3 种基金National Natural Science Foundation of China,Grant/Award Numbers:11704068,61774034the Fundamental Research Funds for the Central Universities,Grant/Award Number:2242019R20025The National Key Research and Development Program of China,Grant/Award Number:2017YFA0205700the Strategic Priority Research Program of Chinese Academy of Sciences,Grant/Award Number:XDB30000000。
文摘Motion tracking has attracted great attention in the fields of real-time tracking,nanorobotics,and targeted therapy.For achieving more accurate motion tracking,the highly sensitive position-sensitive detector(PSD)is desirable.Here,we demonstrate a meliorated PSD based on graphene-Si heterojunction for motion tracking.The position sensitivity of PSD was improved by employing surface engineering of graphene.Through modulating the transport property of graphene,nearly 20-fold increase of sensitivity was achieved under weak light,and at the same time,the detection limit power was reduced to^2 nW.A motion tracking system was developed based on the improved PSD,and human arm swing was tracked,which demonstrated high sensitivity and real-time tracking capabilities of the PSD.In addition,the PSD can support up to^10 kHz high-frequency tracking.This work provides a new strategy for improving the performance of PSD,and promotes the development of two-dimensional materials in novel optoelectronic devices.
基金supported by the National Key Research and Development Program of China(Grant No.2018YFB0406500)the National Natural Science Foundation of China(Grant Nos.61804136,U1804155,and U1604263)the China Postdoctoral Science Foundation(Grant Nos.2018M630829,and 2019T120630)。
文摘Monoclinic Ga2O3(β-Ga2O3)is a promising material for achieving solar-blind photodetection because of its unique characteristics,including its high breakdown electric field,radiation hardness,thermal and chemical stabilities,and intrinsic visible/solar-blind properties.Until now,several studies have investigated the development of high-performanceβ-Ga2O3 solar-blind photodetectors.However,these photodetectors can only detect the light intensity but not the light position.In this work,fourquadrant position-sensitive detectors(4Q-PSDs)were developed and demonstrated based onβ-Ga2O3.4Q-PSDs,comprising four identical metal-semiconductor-metal-structured photodetector components,demonstrate high uniformity,large signal-tonoise ratio,good ultraviolet/visible rejection ratio,and fast response/recovery time.Subsequently,the position of the illumination beam can be determined by analyzing the output signals of the four photodetector components.This work may indicate the promising application potential of the Ga2O3-based photodetectors in the fields of positioning,aligning,and monitoring the solarblind beams.
基金This work was financially supported by Henan Center for Outstanding Overseas Scientists(No.GZS201903)the National Natural Science Foundation of China(Nos.61804136,11974317,and 62027816)+2 种基金Henan Science Fund for Distinguished Young Scholars(No.212300410020)Key Project of Henan Higher Education(No.21A140001)the Zhengzhou University Physics Discipline Improvement Program.
文摘As a typical two-dimensional material,graphitic carbon nitride(g-CN)has attracted great interest because of its distinctive electronic,optical,and catalytic properties.However,the absence of a feasible route toward large-area and high-quality films hinders its development in optoelectronics.Herein,high-quality g-CN films have been grown on Si substrate via a vapor-phase transport-assisted condensation method.The g-CN/Si heterojunction shows an obvious response to ultraviolet–visible-near infrared photons with a responsivity of 133 A·W−1,which is two orders of magnitude higher than the best value ever reported for g-CN photodetectors.A position-sensitive detector(PSD)has been developed using the lateral photovoltaic effect of the g-CN/Si heterojunction.The PSD shows a wide response spectrum ranging from 300 to 1,100 nm,and a position sensitivity and rise/decay time of 395 mV·mm−1 and 3.1/50μs,respectively.Moreover,the application of the g-CN/Si heterojunction photodetector in trajectory tracking and acoustic detection has been realized for the first time.This work unveils the potential of g-CN for large-area photodetectors,and prospects for their applications in trajectory tracking and acoustic detection.
基金supported by the National Natural Science Foundation of China(Nos.11605248,11605249,11605267,and 11805032.)
文摘A foil–microchannel plate(MCP)detector,which uses electrostatic lenses and possesses both good position and timing resolutions,has been designed and simulated for beam diagnostics and mass measurements at the next-generation heavy-ion-beam facility HIAF in China.Characterized by low energy loss and good performances of timing and position measurements,it would be located at focal planes in fragment separator HFRS for position monitoring,beam turning,Bq measurement,and trajectory reconstruction.Moreover,it will benefit the building-up of a magnetic-rigidity–energy-loss–time-offlight(BqDETOF)method at HFRS for high-precision in-flight particle identification of radioactive isotope beams on an event-by-event basis.Most importantly,the detector can be utilized for in-ring TOF and position measurements,beam-line TOF measurements at two achromatic foci,and position measurements at a dispersive focus of HFRS,thus making it possible to use two complementary mass measurement methods[isochronous mass spectrometry at the storage ring SRing and magnetic-rigidity–time-of-flight(BqTOF)at the beam-line HFRS]in one single experimental run.
文摘A Compton camera prototype has been developed using a pixelated CZT detector with 4-by-4 pixels.Signals of the detector are read out by a VASTAT ASIC that is controlled by a self-developed DAQ board. The DAQ software is developed using LabVIEW, and the offline Compton imaging codes are written in C++. The prototype has been successfully calibrated, and its capabilities for source detection, spectroscopy, and Compton imaging have been demonstrated using a Cs-137 source.The angular resolution of the 662 keV line is 36° FWHM for the simple back-projection method and 9.6° FWHM for the MLEM reconstruction method. The system is ready to be extended to 11-by-11 pixels in the future, and a better imaging quality can be expected due to the better relative position resolution.
基金supported by the National Natural Science Foundation of China(No.12235006)the National Key Research and Development Program of China(No.2020YFE0202002.
文摘X-ray detectors show potential applications in medical imaging,materials science,and nuclear energy.To achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorphous selenium,cadmium telluride zinc,and perovskites,have been utilized in direct conversion X-ray detectors.However,these semiconductor materials are susceptible to temperature-induced performance degradation,crystallization,delamination,uneven lattice growth,radiation damage,and high dark current.This study explores a new approach by coupling an FC40 electronic fluorinated liquid with a specialized high-resolution and high-readout-speed complementary metal-oxide-semiconductor(CMOS)pixel array,specifically the Topmetal II−chip,to fabricate a direct conversion X-ray detector.The fluorinated liquid FC40(molecular formula:C_(21)F_(48)N_(2))is an electronic medium that is minimally affected by temperature and displays no issues with uniform conductivity.It exhibits a low dark current and minimal radiation damage and enables customizable thickness in X-ray absorption.This addresses the limitations inherent in conventional semiconductor-based detectors.In this study,simple X-ray detector imaging tests were conducted,demonstrating the excellent coupling capability between FC40 electronic fluorinated liquid and CMOS chips by the X-ray detector.A spatial resolution of 4.0 lp/mm was measured using a striped line par card,and a relatively clear image of a cockroach was displayed in the digital radiography imaging results.Preliminary test results indicated the feasibility of fabricating an X-ray detector by combining FC40 electronic fluorinated liquid and CMOS chips.Owing to the absence of issues related to chip-material coupling,a high spatial resolution could be achieved by reducing the chip pixel size.This method presents a new avenue for studies on novel liquid-based direct conversion X-ray detectors.
基金supported by the National Natural Science Foundation of China(12125505).
文摘The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance.
文摘To detect space gravitational waves in the extremely low-frequency band,the telescope and optic-al platform require high stability and reliability.However,the cantilevered design presents challenges,espe-cially in the glass-metal hetero-bonding process.This study focuses on the analysis and experimental re-search of the bonding layer in the integrated structure.By optimizing the structural configuration and select-ing suitable bonding processes,the reliability of the telescope system is enhanced.The research indicates that using J-133 adhesive achieves the best performance,with a bonding layer thickness of 0.30 mm and a metal substrate surface roughness of Ra 0.8.These findings significantly enhance the reliability of the optical sys-tem while minimizing potential risks.
基金supported by the National Key R&D Program of China(2022YFA1602200)the International Partnership Program of the Chinese Academy of Sciences(211134KYSB20200057).
文摘The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled hyperonantihyperon pairs to be produced at Super Tau-Charm Facility(STCF),the CP asymmetry of hyperon is expected to be tested with a statistical sensitivity of 10^(−4) or even better.To cope with the statistical precision,the systematic effects from various aspects are critical and need to be studied in detail.In this paper,the sensitivity effects on the CP violation parameters associated with the detector resolution,including those of the position and momentum,are studied and discussed in detail.The results provide valuable guidance for the design of STCF detector.
文摘For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchmark construction.This paper proposes an architecture for detecting detector flatness based on channel spectral dispersion.By measuring the dispersion fringes for coplanar adjustment,the final adjustment residual is improved to better than 300 nm.This result validates the feasibility of the proposed technology and provides significant technical support for the development of next-generation large-aperture sky survey equipment.
文摘Radiation doses to patients in diagnostics and interventional radiology need to be optimized to comply with the principles of radiation protection in medical practice. This involves using specific detectors with respective diagnostic beams to carry out quality control/quality assurance tests needed to optimize patient doses in the hospital. Semiconductor detectors are used in dosimetry to verify the equipment performance and dose to patients. This work aims to assess the performance, energy dependence, and response of five commercially available semiconductor detectors in RQR, RQR-M, RQA, and RQT at Secondary Standard Dosimetry for clinical applications. The diagnostic beams were generated using Exradin A4 reference ion chamber and PTW electrometer. The ambient temperature and pressure were noted for KTP correction. The detectors designed for RQR showed good performance in RQT beams and vice versa. The detectors designed for RQR-M displayed high energy dependency in other diagnostic beams. The type of diagnostic beam quality determines the response of semiconductor detectors. Therefore, a detector should be calibrated according to the beam qualities to be measured.
基金Supported by the National Key Research and Development Program of China(2022YFA1404602)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0580000)+3 种基金the National Natural Science Foundation of China(U23B2045,62305362)the Program of Shanghai Academic/Technology Research Leader(22XD1424400)the Fund of SITP Innovation Foundation(CX-461 and CX-522)Special Project to Seize the Commanding Heights of Science and Technology of Chinese Academy of Sciences,subtopic(GJ0090406-6).
文摘The polarization properties of light are widely applied in imaging,communications,materials analy⁃sis,and life sciences.Various methods have been developed that can measure the polarization information of a target.However,conventional polarization detection systems are often bulky and complex,limiting their poten⁃tial for broader applications.To address the challenges of miniaturization,integrated polarization detectors have been extensively explored in recent years,achieving significant advancements in performance and functionality.In this review,we focus mainly on integrated polarization detectors with innovative features,including infinitely high polarization discrimination,ultrahigh sensitivity to polarization state change,full Stokes parameters measure⁃ment,and simultaneous perception of polarization and other key properties of light.Lastly,we discuss the oppor⁃tunities and challenges for the future development of integrated polarization photodetectors.
基金Project supported by the National Natural Science Foundation of China (Grant No. 12275181)Guangdong Basic and Applied Basic Research Foundation (Grant No. 2022B1515120071)+1 种基金Promotion Project of Scientific Research Capability of Key Construction Disciplines in Guangdong Province (Grant No. 2022ZDJS118)Natural Science Foundation of Top Talent SZTU (Grant No. GDRC202205)。
文摘Position-sensitive neutron detectors play an important role in neutron scattering studies. Detectors based on ~6LiF/ZnS(Ag) scintillator and wave-shifting fiber have the advantages of high neutron detection efficiency, high position resolution,and large-area splicing, and can well meet the requirement of large area neutron detection for neutron diffractometers. An engineering detector prototype based on a ~6LiF/ZnS(Ag) scintillation screen and SiPM array readout was fabricated for the General Purpose Powder Diffractometer of China Spallation Neutron Source(CSNS). The detector has an active area of 196 mm × 444 mm, with a pixel size of 4 mm × 4 mm. The key performances of the detector prototype were tested at the BL20 neutron beam line of CSNS. The test results show that the neutron detection efficiency of the detector was 32% and 42% at wavelengths of 1.4 ? and 2.8 ?, respectively. An interpolated neutron detection efficiency of 40.2% at a wavelength of 2 ? was obtained. The tested neutron efficiency non-uniformity of the detector was 10.2%, which is less than one-half that of the current general purpose powder diffractometer scintillator neutron detectors at CSNS. This work achieves, for the first time, an efficiency uniformity of < 11% in large-area mosaic neutron detectors, alongside significant advancements in electromagnetic interference immunity and cost-effectiveness.
基金supported by the Natural Science Foundation of Gansu Province(No.22JR5RA118)the National Natural Science Foundation of China(Nos.12121005 and U1932138)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB34010000)。
文摘The measurement of low-level radioactivity using high-purity germanium(HPGe)detectors is important in applications such as environmental background radiation,material screening,and rare decays.The dead layers,dead zones,aluminum shell thickness,and diameter of Ge crystals are the most influential factors affecting the performance of HPGe detectors;hence,precise modeling of the physical conditions of the detectors is highly desirable.In this study,the GEANT4 simulation framework with an optimized detector geometry adequately replicated the experimentally recorded spectrum.These detector simulations explored the idea of realizing a dead zone(an inactive volume)at the backend of an n-type coaxial Gecrystal.Using multigamma sources,the effect of true coincidence summing(TCS)on the full energy peak(FEP)efficiency calibration of an HPGe detector was investigated as a function of sample-to-detector distance.Good agreements between the simulated and experimental efficiencies as well as the simulated and analytically calculated summing coincidence correction coefficients were achieved.At a short distance between the source and detector,calculating the correction factors for a strong source posed challenges owing to significant deadtime and pile-up effects of the detection system.The described methodology can efficiently determine summing peak probabilities at short sample-to-detector distances.
基金supported by the National Key Research and Development Project,China(No.2023YFA1606404)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB34010300)+5 种基金the National Natural Science Foundation of China(Nos.12022501,12105329,12475127)the Guangdong Major Project of Basic and Applied Basic Research(No.2021B0301030006)the Research Program of Heavy Ion Science and Technology Key Laboratory,Institute of Modern Physics,Chinese Academy of Sciences(Nos.HIST2024KS04,HIST2024CO04)Longyuan Youth Innovation and Entrepreneurship Talent Project of Gansu Province(No.2024GZT04)State Key Laboratory of Nuclear Physics and Technology,Peking University(No.NPT2023KFY01)the Major Science and Technology Projects in Gansu Province(No.24GD13GA005)。
文摘A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nuclei.The digital data acquisition system enables precise synchronization and processing of complex signals from various detectors,such as plastic scintillators,silicon detectors,and germaniumγdetectors.The system's performance was evaluated using theβdecay of^(32)Ar and its neighboring nuclei,produced via projectile fragmentation at the first Radioactive Ion Beam Line in Lanzhou(RIBLL1).Key measurements,including the half-life,charged-particle spectrum,andγ-ray spectrum,were obtained and compared with previous results for validation.Using the implantation–decay method,the isotopes of interest were implanted into two doublesided silicon strip detectors,where their subsequent decays were measured and correlated with preceding implantations using both position and time information.This detection system has potential for further applications,including the study ofβ-delayed charged-particle decay and direct proton emissions from even more exotic proton-rich nuclei.