ALTERNATIVE EXPLANATION OF SPECULAR OPTICAL-ACTIVITY

Bungay et al. [Phys. Lett. A 174, 335 (1993)] reported observing polar ization plane rotation in optical reflection at normal incidence from GaAs, an effect that they term specular optical activity. Their prefer red interpretation hypothesizes a partially symmetric third-rank bulk tensor arising from nonlocality, even though its existence would viola te time reversibility. We present an alternative explanation based on the derived properties of a nonlocal surface layer that preserves time reversibility. (C) 1998 Optical Society of America.