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911.
Strain-Compensated InGaAs/InAlAs Quantum Cascade Detector of 4.5 μm Operating at Room Temperature 下载免费PDF全文
We present a strain-compensated InP-based InGaAs/InAlAs photovoltaic quantum cascade detector grown by solid source molecular beam epitaxy. The detector is based on a vertical intersubband transition and electron transfer on a cascade of quantum levels which is designed to provide longitudinal optical phonon extraction stairs. By careful structure design and growth, the whole epilayer has a residual strain toward InP substrate of only -2.8× 10^-4. A clear narrow band detection spectrum centered at 4.5 μm has been observed above room temperature for a device with 200/times 200 ×μm^2 square mesa. 相似文献
912.
<正>Compared with the traditional image intensifier with phosphor screen readout,the photon-counting imaging detector with charge induction readout is more beneficial in several aspects(e.g.,good imaging properties and time resolution) to astronomy,reconnaissance,bioluminescence,and materials research.However, the annealing temperature during the tube-making process can affect the properties of the Ge film,and consequently impair the performance of the detector.Therefore,the influence of annealing temperature on Ge film and on the detector is studied in order to determine the crucial parameters.The Ge films are prepared on ceramic and quartz glass by the use of an electron gun.They are analyzed by scanning electron microscope(SEM),high-resistance meter,and X-ray diffraction(XRD).The results show that the optimum substrate and annealing temperature are ceramic plate and 250℃,respectively. 相似文献
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据2006年8月25日英国New Scientist的网站报道,一些天文学家对这次国际天文学会(IAU)按照对行星所下新的定义将冥王星降格为“矮行星”颇有微词.执行新视野号冥王星及其卫星探测器任务的美国宇航局的科学家斯特恩(Alan Stem)认为: 相似文献
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XiangQinLIN LiPingLU XiaoHuaJIANG 《中国化学快报》2005,16(3):416-418
A unique method for preparing a coaxial dual-microelectrode sensor by vaporizing the nano-thickness Au layer on the DNA modified carbon fiber micro-column electrode was illustrated. The dual-electrode showed particular merit for determination in biological systems. 相似文献
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为了测量在神舟飞船返回舱内由空间重电离粒子引起的辐射剂量,采用了固体核径迹探测器CR-39来测量飞船飞行期间,返回舱内由重电离粒子引起的能量沉积. 本文介绍了CR-39探测器对能量沉积的响应的刻度. 相似文献
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G. Sher M.I. Shahzad M. Hussain M. A. Rana E. U. Khan 《中国物理快报》2006,23(3):572-575
We investigate the cross section of the heavy ion reaction (14.5 MeV/u) ^132Xe + Bi by using a CR-39 plastic track detector. The target-detector assembly is exposed at UNILAC beam facility of GSI, Germany. After etching under appropriate etching conditions, the detector is scanned for multipronged events produced as a result of interactions of projectile ions with target atoms. The elastic events are separated from binary events and used for the determination of the quarter-point angle. The quarter-point angle obtained is used to determine the total reaction cross section. The total experimental reaction cross section is determined by using statistics of inelastic events of two-pronged and higher multiplicity events. The experimental reaction cross sections determined by using elastic and inelastic data observed in the reaction under study are found to be in good agreement with the theoretically calculated value of reaction cross section using a sharp cutoff model. 相似文献