In the realm of optoelectronics,photodetectors play pivotal roles,with applications spanning from high-speed data communication to precise environmental sensing.Despite the advancements,conventional photodetectors gra...In the realm of optoelectronics,photodetectors play pivotal roles,with applications spanning from high-speed data communication to precise environmental sensing.Despite the advancements,conventional photodetectors grapple with challenges with response speed and dark current.In this study,we present a photodetector based on a lateral MoTe_(2)p-n junction,defined by a semi-floating ferroelectric gate.The strong ferroelectric fields and the depletion region of the p-n junction in the device are notably compact,which diminish the carrier transit time,thereby enhancing the speed of the photoelectric response.The non-volatile MoTe_(2)homojunction,under the influence of external gate voltage pulses,can alter the orientation of the intrinsic electric field within the junction.As a photovoltaic detector,it achieves an ultra-low dark current of 20 pA,and a fast photo response of 2μs.The spectral response is extended to the shortwave infrared range at 1550 nm.Furthermore,a logic computing system with light/no light as binary input is designed to convert the current signal to the voltage output.This research not only underscores the versatility of 2D materials in the realm of sophisticated photodetector design but also heralds new avenues for their application in energy-efficient,high-performance optoelectronic devices.展开更多
随着物联网技术的发展,目前的物联网系统产生的数据量越来越多,这些数据持续不断的传输到数据中心,传统的物联网数据处理分析系统效率低下且无法处理数量如此庞大的数据流.另外,物联网智能设备存在资源受限的特性,在分析数据时这一特性...随着物联网技术的发展,目前的物联网系统产生的数据量越来越多,这些数据持续不断的传输到数据中心,传统的物联网数据处理分析系统效率低下且无法处理数量如此庞大的数据流.另外,物联网智能设备存在资源受限的特性,在分析数据时这一特性是不可忽略的.提出一种适用于物联网实时数据流处理的新架构ApproxECIoT(approximate edge computing Internet of Things),实现了一种自调整分层采样算法,用于处理物联网系统中产生的实时数据流.该算法在维持已给出的资源预算不变的情况下,根据每层方差的大小进行样本层内大小的调整,这对于资源有限的情况下提高计算结果准确度是非常有益的.最后使用模拟数据流和真实数据流进行实验分析,结果表明ApproxECIoT在边缘节点资源有限的情况下,仍能获得具有较高准确度的计算结果.展开更多
为探究冻融循环下纳米黏土对滨海水泥土微观结构的改性效果,通过扫描电子显微镜微观测试对土体微观结构变化规律进行分析,探讨了土体的微观结构定量化参数与宏观力学特征的关联性。以纳米滨海水泥土为对象,利用扫描电子显微镜和Image Pr...为探究冻融循环下纳米黏土对滨海水泥土微观结构的改性效果,通过扫描电子显微镜微观测试对土体微观结构变化规律进行分析,探讨了土体的微观结构定量化参数与宏观力学特征的关联性。以纳米滨海水泥土为对象,利用扫描电子显微镜和Image Pro Plus软件获取土体在0、1、5、7、9、11次的冻融循环下的微观结构特征和量化参数。结果表明:①在未冻融的环境下,纳米黏土改善滨海水泥土微观结构效果明显,孔隙明显减小。②在冻融环境下,纳米黏土在冻融循环初期对滨海水泥土微观结构的改性效果好,表现在冻融循环0~5次内孔隙面积平均减少14.3%,而冻融循环7~11次时仅平均减少4.3%的孔隙面积。通过概率密度函数的分布可知纳米黏土抑制了滨海水泥土超大孔隙的发育。③纳米滨海水泥土的压缩系数对颗粒面积变化比较敏感,颗粒的数量、不均匀系数等微观结构参数对压缩系数的影响较小。展开更多
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0580000)Natural Science Foundation of China(62222413,62025405,62105100,62075228 and 62334001)+1 种基金Natural Science Foundation of Shanghai(23ZR1473400)Hundred Talents Program of the Chinese Academy of Sciences。
文摘In the realm of optoelectronics,photodetectors play pivotal roles,with applications spanning from high-speed data communication to precise environmental sensing.Despite the advancements,conventional photodetectors grapple with challenges with response speed and dark current.In this study,we present a photodetector based on a lateral MoTe_(2)p-n junction,defined by a semi-floating ferroelectric gate.The strong ferroelectric fields and the depletion region of the p-n junction in the device are notably compact,which diminish the carrier transit time,thereby enhancing the speed of the photoelectric response.The non-volatile MoTe_(2)homojunction,under the influence of external gate voltage pulses,can alter the orientation of the intrinsic electric field within the junction.As a photovoltaic detector,it achieves an ultra-low dark current of 20 pA,and a fast photo response of 2μs.The spectral response is extended to the shortwave infrared range at 1550 nm.Furthermore,a logic computing system with light/no light as binary input is designed to convert the current signal to the voltage output.This research not only underscores the versatility of 2D materials in the realm of sophisticated photodetector design but also heralds new avenues for their application in energy-efficient,high-performance optoelectronic devices.
文摘随着物联网技术的发展,目前的物联网系统产生的数据量越来越多,这些数据持续不断的传输到数据中心,传统的物联网数据处理分析系统效率低下且无法处理数量如此庞大的数据流.另外,物联网智能设备存在资源受限的特性,在分析数据时这一特性是不可忽略的.提出一种适用于物联网实时数据流处理的新架构ApproxECIoT(approximate edge computing Internet of Things),实现了一种自调整分层采样算法,用于处理物联网系统中产生的实时数据流.该算法在维持已给出的资源预算不变的情况下,根据每层方差的大小进行样本层内大小的调整,这对于资源有限的情况下提高计算结果准确度是非常有益的.最后使用模拟数据流和真实数据流进行实验分析,结果表明ApproxECIoT在边缘节点资源有限的情况下,仍能获得具有较高准确度的计算结果.
文摘为探究冻融循环下纳米黏土对滨海水泥土微观结构的改性效果,通过扫描电子显微镜微观测试对土体微观结构变化规律进行分析,探讨了土体的微观结构定量化参数与宏观力学特征的关联性。以纳米滨海水泥土为对象,利用扫描电子显微镜和Image Pro Plus软件获取土体在0、1、5、7、9、11次的冻融循环下的微观结构特征和量化参数。结果表明:①在未冻融的环境下,纳米黏土改善滨海水泥土微观结构效果明显,孔隙明显减小。②在冻融环境下,纳米黏土在冻融循环初期对滨海水泥土微观结构的改性效果好,表现在冻融循环0~5次内孔隙面积平均减少14.3%,而冻融循环7~11次时仅平均减少4.3%的孔隙面积。通过概率密度函数的分布可知纳米黏土抑制了滨海水泥土超大孔隙的发育。③纳米滨海水泥土的压缩系数对颗粒面积变化比较敏感,颗粒的数量、不均匀系数等微观结构参数对压缩系数的影响较小。
