Journal of Nonlinear Optical Physics & Materials
THERMAL RELAXATION TIMES OF BISTABLE THIN FILM ELEMENTS
Veronika Glaw, Klemens Janiak, A. Kummrow, Volker Penschke, Hans-Joachim Eichler
Abstract
The heat flow in evaporated thin film interference filters with CdS spacer and an optional CdSe absorption layer is investigated, analyzing the dynamics of optical bistability. The influence of the spot radius r of the exciting laser beam on the switching parameters is studied experimentally and theoretically. The response to pulsed excitation of the bistable devices can be described with a relaxation time τ~r and an effective nonlinearity χ~r−2 which is inversely proportional to the heat capacity of the bistable element.