Accession Number : ADP007839
Title : An Ultimately Low-Threshold Semiconductor Laser with Separate Quantum Confinements for Single Electron-Hole Pair and Single Photon Field,
Corporate Author : HIROSHIMA UNIV (JAPAN)
Personal Author(s) : Yamanishi, Masamichi ; Yamamoto, Yoshihisa
Report Date : 22 MAY 1992
Pagination or Media Count : 4
Abstract : The threshold pump rate Pth, of a laser is determined by three factors: coupling efficiency Beta of spontaneous emission into a lasing mode, a population inversion parameter nsp for a given pump rate, and photon decay rate gamma (or a photon lifetime Tp=l/gamma), i.e., Pth,=gamma sub sp/IBeta. The population inversion parameter nsp is given by n, sub/sp=Ecv/(Ecv-Ecv) where Ecv and Evc are stimulated emission and absorption rates for one photon in a lasing mode, respectively. The value of Beta is on the order of 10-4 to 10-5 for a conventional semiconductor laser. To decrease the threshold pump rate Pth, we can increase Beta close to one by using a single-mode cavity.
Descriptors : *SEMICONDUCTOR LASERS, *QUANTUM EFFICIENCY, *OPTICAL PUMPING, CAVITIES, COUPLINGS, DECAY, EFFICIENCY, EMISSION, INVERSION, LASERS, PARAMETERS, PHOTONS, POPULATION, RATES, VALUE, JAPAN, RADIATION ABSORPTION.
Subject Categories : Lasers and Masers
Electrooptical and Optoelectronic Devices
Distribution Statement : APPROVED FOR PUBLIC RELEASE