An innovative gas sensor with on-chip reference using a monolithic twin laser is proposed. In this sensor a monolithic twin laser generates two closer laser beams with slight different wavelengths alternatively, one p...An innovative gas sensor with on-chip reference using a monolithic twin laser is proposed. In this sensor a monolithic twin laser generates two closer laser beams with slight different wavelengths alternatively, one photodiode is used to catch both absorption and reference signals by time division multiplexing. The detection of nitrous oxide adopting this scheme using a 2.1 I^m antimonide laser and an InGaAs photodiode has been demonstrated experimentally with detection limit below i ppm. Using this on chip reference scheme the fluctuations from the optical path and devices can be compensated effectively; the sensor system is simplified distinctly.展开更多
A wireless terahertz （THz） communication link is demonstrated, in which a THz quantum cascade laser and a THz quantum-well photo-detector （QWP） serve as the emitter and receiver, respectively. With the help of the...A wireless terahertz （THz） communication link is demonstrated, in which a THz quantum cascade laser and a THz quantum-well photo-detector （QWP） serve as the emitter and receiver, respectively. With the help of the well-matched THz QWP, the optical collection efficiency has greatly been improved. A data signal transmitted over 2.2 m with a low bit error rate （≤1 × 10^-8） and data rate as high as 20 Mbps is achieved, which are almost 1 order of magnitude higher than that previously reported.展开更多
We demonstrate a wireless transmission link at 3.9 THz over a distance of 0.5 m by employing a terahertz （Hz） quantum-cascade laser （QCL） and a THz quantum-well photodetector （QWP）. We make direct voltage modula...We demonstrate a wireless transmission link at 3.9 THz over a distance of 0.5 m by employing a terahertz （Hz） quantum-cascade laser （QCL） and a THz quantum-well photodetector （QWP）. We make direct voltage modulation of the THz QCL and use a spectral-matched THz QWP to detect the modulated THz light from the laser. The small signal model and a direct voltage modulation scheme of the laser are presented. A square wave up to 30 MHz is added to the laser and detected by the THz detector. The bandwidth limit of the wireless link is also discussed.展开更多
A 2.4-m communication link operating at 3.9 THz based on a terahertz quantum cascade laser and a terahertz quantum well photodetector （THz QWP） are introduced. The lumped electrical models of THz QWP for small signa...A 2.4-m communication link operating at 3.9 THz based on a terahertz quantum cascade laser and a terahertz quantum well photodetector （THz QWP） are introduced. The lumped electrical models of THz QWP for small signals are presented. A discussion of the bandwidth limit of the detecting circuit is presented. Using direct on off-keying modulation and intensity detection, the transmission of digital video signal with a data rate of 2.5 Mb/s is demonstrated. Pseudo-random binary sequences are transmitted to investigate the bit-error rate （BER） at different rates. Result shows the error free transmission when the rate is below 5 Mb/s.展开更多
基金the support from the Alexander von Humboldt Foundationsupported by the National Basic Research Program of China(Grant No.2007CB310402)+4 种基金the 863 program of Chinathe National Natural Science Foundation of China(Grant No.60721004)the major projects(Project Nos.KGCX1-YW-24 and KGCX2-YW-231)the Hundred Talent Program of the Chinese Academy of Sciencesthe Shanghai Municipal Commission of Science and Technology(Project No.10JC1417000)
文摘An innovative gas sensor with on-chip reference using a monolithic twin laser is proposed. In this sensor a monolithic twin laser generates two closer laser beams with slight different wavelengths alternatively, one photodiode is used to catch both absorption and reference signals by time division multiplexing. The detection of nitrous oxide adopting this scheme using a 2.1 I^m antimonide laser and an InGaAs photodiode has been demonstrated experimentally with detection limit below i ppm. Using this on chip reference scheme the fluctuations from the optical path and devices can be compensated effectively; the sensor system is simplified distinctly.
基金supported by the National"973"Program of China(No.2014CB339803)the National"863"Program of China(No.2011AA010205)+5 种基金the National Natural Science Foundation of China(Nos.61131006,61321492,61176086,61204135,61306066,61404149,61404150,and 61204135)the Major National Development Project of Scientific Instrument and Equipment(No.2011YQ150021)the National Science and Technology Major Project(No.2011ZX02707)the Major Project(No.YYYJ-1123-1)the International Collaboration and Innovation Program on High Mobility Materials Engineering of the Chinese Academy of Sciencesthe Shanghai Municipal Commission of Science and Technology(Nos.13ZR1464600 and14ZR1447400)
文摘A wireless terahertz （THz） communication link is demonstrated, in which a THz quantum cascade laser and a THz quantum-well photo-detector （QWP） serve as the emitter and receiver, respectively. With the help of the well-matched THz QWP, the optical collection efficiency has greatly been improved. A data signal transmitted over 2.2 m with a low bit error rate （≤1 × 10^-8） and data rate as high as 20 Mbps is achieved, which are almost 1 order of magnitude higher than that previously reported.
基金supported by the National 973 Program of China(No.2014CB339803)the National 863 Program of China(No.2011AA010205)+4 种基金the National Natural Science Foundation of China(Nos.61131006,61321492,61176086,61204135,and 61306066)the Major National Development Project of Scientific Instrument and Equipment(No.2011YQ150021)the National Science and Technology Major Project(No.2011ZX02707)the Major Project(No.YYYJ1123-1)the International Collaboration and Innovation Program on High Mobility Materials Engineering of the Chinese Academy of Sciences and the Shanghai Municipal Commission of Science and Technology(No.13ZR1464600)
文摘We demonstrate a wireless transmission link at 3.9 THz over a distance of 0.5 m by employing a terahertz （Hz） quantum-cascade laser （QCL） and a THz quantum-well photodetector （QWP）. We make direct voltage modulation of the THz QCL and use a spectral-matched THz QWP to detect the modulated THz light from the laser. The small signal model and a direct voltage modulation scheme of the laser are presented. A square wave up to 30 MHz is added to the laser and detected by the THz detector. The bandwidth limit of the wireless link is also discussed.
基金supported by the National"863"Pro-gram of China(No.2011AA010205)the National Natural Science Foundation of China(Nos.61131006,6117 6086,and 61204135)+3 种基金the Major National Development Project of Scientific Instrument and Equipment(No.2011YQ150021)the Important National Science and Technology Specific Projects(No.2011ZX02707)the Major Project(No.YYYJ-1123-1)the International Collaboration and Innovation Program on High Mobility Materials Engineering of Chinese Academy of Sciences,and the Shanghai Municipal Commission of Sci-ence and Technology(Nos.10JC1417000,11ZR1444000,and 11ZR1444200)
文摘A 2.4-m communication link operating at 3.9 THz based on a terahertz quantum cascade laser and a terahertz quantum well photodetector （THz QWP） are introduced. The lumped electrical models of THz QWP for small signals are presented. A discussion of the bandwidth limit of the detecting circuit is presented. Using direct on off-keying modulation and intensity detection, the transmission of digital video signal with a data rate of 2.5 Mb/s is demonstrated. Pseudo-random binary sequences are transmitted to investigate the bit-error rate （BER） at different rates. Result shows the error free transmission when the rate is below 5 Mb/s.
