An optical spectroscopy for detecting quantized polarization waves of excitons

Abstract

An optical spectroscopy, based upon the determination of the difference between the reflectivity for p-polarized light (R-p) and the squared reflectivity for s-polarized light (R-s(2)) with an angle of incidence of 45 degrees, is proposed to study the interaction of excitons with the surface potential in semiconductors, It is found that R-p - R-s(2) as a function of the wave frequency is quite sensitive to the form of the surface potential. In addition, the generation of longitudinal modes such as the quantized polarization waves of excitons produces resonant dips well-identified in the new spectrum. On the other hand, the transverse resonances present in R-p and R-s disappear in the difference R-p-R-s(2). (C) 1997 American Institute of Physics.