Neuromorphic vision hardware,embedded with multiple functions,has recently emerged as a potent platform for machine vision.To realize memory in sensor functions,reconfigurable and non-volatile manipulation of photocar...Neuromorphic vision hardware,embedded with multiple functions,has recently emerged as a potent platform for machine vision.To realize memory in sensor functions,reconfigurable and non-volatile manipulation of photocarriers is highly desirable.However,previous technologies bear mechanism challenges,such as the ambiguous optoelectronic memory mechanism and high potential barrier,resulting in a limited response speed and a high operating voltage.Here,for the first time,we propose a critical band-to-band tunnelling(BTBT)based device that combines sensing,integration and memory functions.The nearly infinitesimal barrier facilitates the tunnelling process,resulting in a broadband application range(94o nm).Furthermore,the observation of dual negative differential resistance(NDR)points confirms that the critical BTBT of photocarriers contributes to the sub-microsecond photomemory speed.Since the photomemory speed,with no motion blur,is important for motion detection,the critical BTBT memory is expected to enable moving target tracking and recognition,underscoring its superiority in intelligentperception.展开更多
Inorganic perovskitenanostructures have attracted considerable attention for their tunable band gaps and excellent optoelectronic properties.It is inevitable that phase segregation of halide perovskite usually occurs ...Inorganic perovskitenanostructures have attracted considerable attention for their tunable band gaps and excellent optoelectronic properties.It is inevitable that phase segregation of halide perovskite usually occurs in mixed-halide perovskites under a focused laser llumination,which caused by photo-induced halide-ion segregation.Here,we reported an uniform perovskite alloy nanowires via a chemical vapor deposition(CvD)method.Microstructural characterization reveals that these perovskite nanowires have independent linear morphology_with high-quality crystalline.Micro-photoluminescence(PL)spectra exhibit that these nanowire structures show a dual-wavelength emissions at 690 and 570 nm,respectively.Additionally,time-dependent PL intensity of the emission peak at 690 nm increased by the decrease of the emission peak at 570 nm under a focused laser llumination,indicating the formation of phase segregation at the excited positions.Moreover,based on these as-grown halide perovskite CsPbBr2.52lo.48 nanowires,a reasonably optical switch is designed and constructed.This optical switch may have potential applications in timed blasting system and time-delay circuit in the future.展开更多
Bandgap engineering of semiconductor nanowires or nanoribbons(NRs)offers a promising material foundation for multifunctional integrated optoelectronic devices and circuits.Among these materials,all-inorganic halide pe...Bandgap engineering of semiconductor nanowires or nanoribbons(NRs)offers a promising material foundation for multifunctional integrated optoelectronic devices and circuits.Among these materials,all-inorganic halide perovskites have emerged as a leading candidate for next-generation photoelectronic applications due to their outstanding optoelectronic properties.In this work,we report the direct synthesis of high-quality bandgap gradient lead halide perovskite(CsPbCl_(3−3x)Br_(3x)and CsPbBr_(3−3x)I_(3x)(x=0-1))NRs using a magnetic-pulling source-moving chemical-vapor-deposition(CVD)method.Microstructural characterizations reveal that these as-grown NRs possess high-quality single crystalline structures with continuously tunable compositions.The photoluminescence emissions of these perovskite NRs can be finely tuned across the entire visible spectrum(417-702 nm).Furthermore,photodetectors based on these perovskite NRs demonstrate exceptional photoelectric performance,including a high I_(ON)/I_(OFF)ratio(10^(4)),superior responsivity(37.5 A/W),and remarkable detectivity(2.81×10^(13)Jones).A spatially resolved imaging sensor based on these perovskite NRs is also demonstrated,indicating promising applications in photoelectronic imaging circuits.These bandgap-tunable perovskite NRs provide a versatile materials platform for future integrated devices in electronics and optoelectronics.展开更多
基金supported by the National Key Research and Development Programme of China(Grant No.2023YFB3611400)National Natural Science Foundation of China(Grant Nos.62327812,62361136587,62422410,62205360 and 62304229)+2 种基金Shanghai Rising-Star Programme(Grant No.24QA2711000)CAS Project for Young Scientists in Basic Research(Grant No.YSBR-113)CAS Pioneer Hundred Talents Program.
文摘Neuromorphic vision hardware,embedded with multiple functions,has recently emerged as a potent platform for machine vision.To realize memory in sensor functions,reconfigurable and non-volatile manipulation of photocarriers is highly desirable.However,previous technologies bear mechanism challenges,such as the ambiguous optoelectronic memory mechanism and high potential barrier,resulting in a limited response speed and a high operating voltage.Here,for the first time,we propose a critical band-to-band tunnelling(BTBT)based device that combines sensing,integration and memory functions.The nearly infinitesimal barrier facilitates the tunnelling process,resulting in a broadband application range(94o nm).Furthermore,the observation of dual negative differential resistance(NDR)points confirms that the critical BTBT of photocarriers contributes to the sub-microsecond photomemory speed.Since the photomemory speed,with no motion blur,is important for motion detection,the critical BTBT memory is expected to enable moving target tracking and recognition,underscoring its superiority in intelligentperception.
基金The authors are grateful to the National Natural Science Foundation of China(No.52373246)the Fundamental Research Program of Shanxi Provinces(No.20210302123128)the National Key Research and Development Program of China(No.2022YFA1404201)for financial support.
文摘Inorganic perovskitenanostructures have attracted considerable attention for their tunable band gaps and excellent optoelectronic properties.It is inevitable that phase segregation of halide perovskite usually occurs in mixed-halide perovskites under a focused laser llumination,which caused by photo-induced halide-ion segregation.Here,we reported an uniform perovskite alloy nanowires via a chemical vapor deposition(CvD)method.Microstructural characterization reveals that these perovskite nanowires have independent linear morphology_with high-quality crystalline.Micro-photoluminescence(PL)spectra exhibit that these nanowire structures show a dual-wavelength emissions at 690 and 570 nm,respectively.Additionally,time-dependent PL intensity of the emission peak at 690 nm increased by the decrease of the emission peak at 570 nm under a focused laser llumination,indicating the formation of phase segregation at the excited positions.Moreover,based on these as-grown halide perovskite CsPbBr2.52lo.48 nanowires,a reasonably optical switch is designed and constructed.This optical switch may have potential applications in timed blasting system and time-delay circuit in the future.
基金the National Natural Science Foundation of China(Nos.52373246,62127817,and U23A20380)the National Key Research and Development Program of China(No.2022YFA1404201)+2 种基金Science and Technology Major Special Project of Shanxi Province(No.202201010101005)the Shanxi Province Graduate Innovation Project(No.RC2400005577)the Shanxi Basic Research Program Project(No.20210302123128)for financial support.
文摘Bandgap engineering of semiconductor nanowires or nanoribbons(NRs)offers a promising material foundation for multifunctional integrated optoelectronic devices and circuits.Among these materials,all-inorganic halide perovskites have emerged as a leading candidate for next-generation photoelectronic applications due to their outstanding optoelectronic properties.In this work,we report the direct synthesis of high-quality bandgap gradient lead halide perovskite(CsPbCl_(3−3x)Br_(3x)and CsPbBr_(3−3x)I_(3x)(x=0-1))NRs using a magnetic-pulling source-moving chemical-vapor-deposition(CVD)method.Microstructural characterizations reveal that these as-grown NRs possess high-quality single crystalline structures with continuously tunable compositions.The photoluminescence emissions of these perovskite NRs can be finely tuned across the entire visible spectrum(417-702 nm).Furthermore,photodetectors based on these perovskite NRs demonstrate exceptional photoelectric performance,including a high I_(ON)/I_(OFF)ratio(10^(4)),superior responsivity(37.5 A/W),and remarkable detectivity(2.81×10^(13)Jones).A spatially resolved imaging sensor based on these perovskite NRs is also demonstrated,indicating promising applications in photoelectronic imaging circuits.These bandgap-tunable perovskite NRs provide a versatile materials platform for future integrated devices in electronics and optoelectronics.
