A pressure measurement and compensation technique was studied by employing a 3.291 μm Continuous Wave (CW) Interband Cascade Laser (ICL) and a dense-patterned Multipass Gas Cell (MPGC) with an effective optical path ...A pressure measurement and compensation technique was studied by employing a 3.291 μm Continuous Wave (CW) Interband Cascade Laser (ICL) and a dense-patterned Multipass Gas Cell (MPGC) with an effective optical path length of 54.6 m. The pressure inside the MPGC was measured based on direct Lorentzian absorption line fitting on the measured absorption spectral signal of CH4, and then pressure compensation was made on the masured CH4 concentration. Pressure calibration was performed from 1.33 ×10^(4) Pa to 10.64 ×10^(4) Pa using a 2.1×10^(6)CH4 sample. An Allan deviation analysis of the measured pressure of a 2.1×10^0 6 CH4 at 9.31×10^(4) Pa pressure indicates a measurement precision of -219.5 Pa with a 2. 2 s averaging time. Fiveteen groups of pressure/concentration measurements of 1.0 ×10^(-6), 1.2×10^(-6), 1.4×10^(-6), 1.6×10^(-6)and 2.1×10^(-6)CH4 samples at different pressures of 1.33×10^(4), 3.99×10^(4) and 6.65 ×10^(4) Pa were performed, and the results proved the feasibility of the proposed pressure measurement and compensation technique.展开更多
The rapid development of modern infrared optoelectronic technology has driven a growing demand for high-sensitivity mid-wave infrared(MWIR)photodetectors capable of reliable room-temperature operation.Achieving optima...The rapid development of modern infrared optoelectronic technology has driven a growing demand for high-sensitivity mid-wave infrared(MWIR)photodetectors capable of reliable room-temperature operation.Achieving optimal specific detectivity,a critical performance metric for MWIR photodetection,remains challenging due to inherent limitations imposed such as high dark current,low optical absorption,or both.To address these challenges,we present an approach based on a bipolar-barrier architecture featuring a black phosphorus(BP)/MoTe_(2)/BP tunnel heterostructure integrated with an Au reflector.This configuration delivers simultaneous electrical and optical enhancement,effectively suppressing dark currents and significantly increasing optical absorption.The bipolar-barrier structure minimizes dark current by blocking thermally excited and bias-induced carrier leakage,while facilitating efficient tunneling of photogenerated carriers via trap-assisted photogating mechanisms.In addition,the Au reflector enhances optical absorption through interference effects.As a result,the heterostructure achieves remarkable performance metrics,including a room-temperature specific detectivity of~3.0×10^(10)cm Hz0.5 W^(-1),a high responsivity of~4 A W^(-1),and an external quantum efficiency of~140%within the MWIR range.These results establish the bipolar-barrier tunnel heterostructure as a highly efficient platform,paving the way for the next generation of advanced infrared optoelectronic devices.展开更多
根据CO分子在中红外波段的吸收特性,利用红外热辐射光源(IR55)和双通道热释电探测器(LM244),研制了一种差分式CO检测仪。通过双通道锁相放大器对探测器输出的两路信号进行处理,有效地抑制了系统噪声,提高了仪器的检测精度。介绍了系统...根据CO分子在中红外波段的吸收特性,利用红外热辐射光源(IR55)和双通道热释电探测器(LM244),研制了一种差分式CO检测仪。通过双通道锁相放大器对探测器输出的两路信号进行处理,有效地抑制了系统噪声,提高了仪器的检测精度。介绍了系统的检测原理,给出了光学系统和双通道锁相放大器的实现方案,该锁相放大器能提取的最小标准信号幅度为1 m V,移相误差小于0.2%。利用配备的体积分数为0~1×10^(-3)的CO样品,开展了气体检测实验。实验结果表明:系统的检测下限为1×10^(-5),相对测量误差小于15%。当气体体积分数为0×10^(-6)时,测得浓度的波动范围为-5.2×10^(-6)~6.2×10^(-6)。考虑静态配气时气体在气室中扩散的时间,仪器的响应时间约为58~62 s。同基于量子级联激光器和分布反馈激光器的CO检测仪相比,所研制的仪器具有结构简单、性价比高等优势,在煤矿、环保等场合的CO检测方面具有较好的应用前景。展开更多
基金The National Key R&D Program of China(Nos.2016YFD0700101,2016YFC0303902,2017YFB0402800)National Natural Science Foundation of China(Nos.61775079,61627823,61307124)+1 种基金Science and Technology Department of Jilin Province of China(Nos.20140307014SF20140307014SF,2017C027)Changchun Municipal Science and Technology Bureau(No.14KG022)
文摘A pressure measurement and compensation technique was studied by employing a 3.291 μm Continuous Wave (CW) Interband Cascade Laser (ICL) and a dense-patterned Multipass Gas Cell (MPGC) with an effective optical path length of 54.6 m. The pressure inside the MPGC was measured based on direct Lorentzian absorption line fitting on the measured absorption spectral signal of CH4, and then pressure compensation was made on the masured CH4 concentration. Pressure calibration was performed from 1.33 ×10^(4) Pa to 10.64 ×10^(4) Pa using a 2.1×10^(6)CH4 sample. An Allan deviation analysis of the measured pressure of a 2.1×10^0 6 CH4 at 9.31×10^(4) Pa pressure indicates a measurement precision of -219.5 Pa with a 2. 2 s averaging time. Fiveteen groups of pressure/concentration measurements of 1.0 ×10^(-6), 1.2×10^(-6), 1.4×10^(-6), 1.6×10^(-6)and 2.1×10^(-6)CH4 samples at different pressures of 1.33×10^(4), 3.99×10^(4) and 6.65 ×10^(4) Pa were performed, and the results proved the feasibility of the proposed pressure measurement and compensation technique.
基金supported by the Singapore Agency for Science,Technology and Research(A*STAR)(M22K2c0080,R23I0IR041 and M23M2b0056)National Research Foundation Singapore(Award No.NRFCRP22-2019-0007,NRF-CRP29-2022-0003,and NRF-MSG-2023-0002).
文摘The rapid development of modern infrared optoelectronic technology has driven a growing demand for high-sensitivity mid-wave infrared(MWIR)photodetectors capable of reliable room-temperature operation.Achieving optimal specific detectivity,a critical performance metric for MWIR photodetection,remains challenging due to inherent limitations imposed such as high dark current,low optical absorption,or both.To address these challenges,we present an approach based on a bipolar-barrier architecture featuring a black phosphorus(BP)/MoTe_(2)/BP tunnel heterostructure integrated with an Au reflector.This configuration delivers simultaneous electrical and optical enhancement,effectively suppressing dark currents and significantly increasing optical absorption.The bipolar-barrier structure minimizes dark current by blocking thermally excited and bias-induced carrier leakage,while facilitating efficient tunneling of photogenerated carriers via trap-assisted photogating mechanisms.In addition,the Au reflector enhances optical absorption through interference effects.As a result,the heterostructure achieves remarkable performance metrics,including a room-temperature specific detectivity of~3.0×10^(10)cm Hz0.5 W^(-1),a high responsivity of~4 A W^(-1),and an external quantum efficiency of~140%within the MWIR range.These results establish the bipolar-barrier tunnel heterostructure as a highly efficient platform,paving the way for the next generation of advanced infrared optoelectronic devices.
文摘根据CO分子在中红外波段的吸收特性,利用红外热辐射光源(IR55)和双通道热释电探测器(LM244),研制了一种差分式CO检测仪。通过双通道锁相放大器对探测器输出的两路信号进行处理,有效地抑制了系统噪声,提高了仪器的检测精度。介绍了系统的检测原理,给出了光学系统和双通道锁相放大器的实现方案,该锁相放大器能提取的最小标准信号幅度为1 m V,移相误差小于0.2%。利用配备的体积分数为0~1×10^(-3)的CO样品,开展了气体检测实验。实验结果表明:系统的检测下限为1×10^(-5),相对测量误差小于15%。当气体体积分数为0×10^(-6)时,测得浓度的波动范围为-5.2×10^(-6)~6.2×10^(-6)。考虑静态配气时气体在气室中扩散的时间,仪器的响应时间约为58~62 s。同基于量子级联激光器和分布反馈激光器的CO检测仪相比,所研制的仪器具有结构简单、性价比高等优势,在煤矿、环保等场合的CO检测方面具有较好的应用前景。
