INPLANE OPTICAL ANISOTROPY OF GAAS ALAS MULTIPLE-QUANTUM WELLS PROBEDBY MICROSCOPIC REFLECTANCE DIFFERENCE SPECTROSCOPY/

We present a technique, microscopic reflectance difference spectroscop y (mu RDS), for the measurement of optical anisotropy with sub-micron resolution. The technique is applied to the determination of the in-pl ane anisotropy of GaAs/AlAs multiple quantum well structures in a phas e resolved way, both below and above the fundamental gap. Confinement and local field effects are discussed, and a comparison is made with m icroscopic calculations based on a tight-binding Hamiltonian for the e lectronic states. (C) 1996 American Institute of Physics.