Incidence-angle dependence of optical reflectivity difference from an ultrathin film on solid surface

We studied the incidence-angle dependence of the optical reflectivity difference in response to ultrathin films on transparent and opaque substrates. We found that the classical three-layer model reproduces the experimentally obtained angular dependence for a monolayer of xenon on Nb(110) and for a monolayer of protein molecules on functionalized glass. We explore the enhancement of the optical response near the Brewster angle (or its equivalent for opaque substrates) in thin film detection. (c) 2006 Optical Society of America.