Characterization of External Quantum Efficiency and Absorption Efficiency in GaAs/ InGaP Double Heterostructures for Laser Cooling Applications

摘要

The state of current research in laser cooling of semiconductors is reviewed. Emphasis is placed on the characterization of external quantum efficiency and absorption efficiency in GaAs/InGaP double heterostuctures. New experimental results will be presented that characterize device operation as a function of laser excitation power and temperature. Optimum carrier density is obtained independently and used as a screening tool for sample quality. The crucial importance of parasitic background absorption is discussed.