Interband cascade detectors

A device for detecting radiation, typically in the infrared. Photons are absorbed in an active region of a semiconductor device such that the absorption induces an interband electronic transition and generates photo-excited charge carriers. The charge carriers are coupled into a carrier transport region having multiple quantum wells and characterized by intersubband relaxation that provides rapid charge carrier collection. The photo-excited carriers are collected from the carrier transport region at a conducting contact region. Another carrier transport region characterized by interband tunneling for multiple stages draws charge carriers from another conducting contact and replenishes the charge carriers to the active region for photo-excitation. A photocurrent is generated between the conducting contacts through the active region of the device

Short Terahertz Pulses from Semiconductor Surfaces: The Importance of Bulk Difference‐Frequency Mixing

The crystallographic orientation dependence of the far‐infrared (FIR) light generated at the (001) surface of a zincblende semiconductor is shown to derive principally from bulk difference‐frequency mixing. A strong modulation is observed for 1‐GW/cm2 pulses on InP, which demonstrates that the radiated FIR wave produced by bulk optical rectification is comparable to that generated by the transport of photoinjected carriers. Using the bulk rectification light as a clock, we show that more than 95% of the light produced from an InP (111) crystal by 100‐fs, 100‐μJ pulses is generated in a time shorter than the excitation pulse

Temperature Dependence of Electrical and Optical Modulation Responses of Quantum-Well Lasers

We present theory and experiment for high-speed optical injection in the absorption region of a quantum-well laser and compare the results with those of electrical injection including the carrier transport effect. We show that the main difference between the two responses is the low-frequency roll-off. By using both injection methods, we obtain more accurate and consistent measurements of many important dynamic laser parameters, including the differential gain, carrier lifetime, K factor, and gain compression factor. Temperature-dependent data of the test laser are presented which show that the most dominant effect is the linear degradation of differential gain and injection efficiency with increasing temperature. While the K-factor is insensitive to temperature variation for multiple-quantum-well lasers, we find that the carrier capture time and nonlinear gain suppression coefficient decreases as temperature increases

Optical Rectification at Semiconductor Surfaces

We show that far-infrared radiation can be generated in the depletion field near semiconductor surfaces via the inverse Franz-Keldysh effect or electric-field-induced optical rectification. This mechanism is conceptually different from those previously proposed and accounts for many recent experimental observations

Electromagnetic Wave Theory and Remote Sensing

Contains reports on seven research projects.Joint Services Electronics Program (Contract DAAG29-78-C-0020)Joint Services Electronics Program (Contract DAAG29-80-C-0104)National Science Foundation (Grant ENG78-23145)National Aeronautics and Space Administration (Contract NAS5-24139)Schlumberger Doll Research CenterU.S. Air Force - Hanscom (Contract F19628-80-C-0052)National Aeronautics and Space Administration (Contract NAG 5-16)Draper Laboratory (Contract DL-H-182642

Electromagnetic Wave Theory and Remote Sensing

Contains reports on six research projects.Joint Services Electronics Program (Contract DAAG29-80-C-0104)National Science Foundation (Grant ENG78-23145)National Science Foundation (Grant ECS82-03390)Schlumberger-Doll Research CenterNational Aeronautics and Space Administration (Contract NAG 5-141)National Aeronautics and Space Administration (Contract NAS5-26861)National Aeronautics and Space Administration (Contract NAG5-270

Metal-cavity surface-emitting microlaser at room temperature

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 96, 251101 (2010) and may be found at https://doi.org/10.1063/1.3455316.We propose and realize a substrate-free metal-cavity surface-emitting microlaser with both top and sidewall metal and a bottom distributed Bragg reflector as the cavity structure. The transfer-matrix method is used to design the laser structure based on the round-trip resonance condition inside the cavity. The laser is 2.0m in diameter and 2.5m in height, and operates at room temperature with continuous-wave mode. Flip-bonding the device to a silicon substrate with a conductive metal provides efficient heat removal. A high characteristic temperature about 425 K is observed from 10 to 27°C.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, Bauelement

Electromagnetic Wave Theory and Remote Sensing

Contains reports on seven research projects.Joint Services Electronics Program (Contract DAAG29-83-K-0003)National Science Foundation (Grant ECS82-03390)Schlumberger-Doll Research CenterNational Aeronautics and Space Administration (Contract NAG5-141)National Aeronautics and Space Administration (Contract NAS5-26861)National Aeronautics and Space Administration (Contract NAG5-270)U.S. Navy - Office of Naval Research (Contract N00014-83-K-0258

Electromagnetic Wave Theory and Remote Sensing

Contains reports on eight research projects.Joint Services Electronics Program (Contract DAAG29-83-K-0003)National Science Foundation (Grant ECS82-03390)Schlumberger-Doll Research CenterNational Aeronautics and Space Administration (Contract NAG5-141)National Aeronautics and Space Administration (Contract NAS5-26861)National Aeronautics and Space Administration (Contract NAG5-270)U.S. Navy - Office of Naval Research (Contract N00014-83-K-0258)International Business Machines, Inc