Teruhito MISHIMA

Department of Electronic Engineering, Faculty of Engineering, Hokkaido University, Sapporo, 060 Japan

(Received April 13, 1995; Accepted June 30, 1995)

Self-pumped four wave mixing (SPFWM) in a single BaTiO₃ crystal is experimentally studied because of its fast response and rather simple optical system. The origins of unstable operations are shown and classified: unstable operation of self-pumped phase conjugate mirror (SPPCM), floating dust in the laser beam path, competition between beam path loops, and competition between groups of index gratings. The reflectivities and the buildup times are measured as they relate to incident conditions, i.e. the geometry of beam paths and interaction regions, and four cases are given. Large reflectivity was obtained when buildup time was short, probably because of large coupling strength. The measured buildup times lie between 0.5 s and 0.6 s at the total incident beam power of about 5.5 mW, so that fast response of SPFWM was confirmed.

Key words : self-pumped four wave mixing, unstable operation, reflectivity, buildup time, temporal response