SPATIAL OPTICAL PARAMETRIC COUPLING OF PICOSECOND LIGHT-PULSES AND TRANSVERSE RELAXATION EFFECT IN RESONANT MEDIA

The dynamical properties of a third-order nonlinear optical process, in which two incident light pulses with wave vectors k1 and k2 generate a light wave with 2k2–k1 in resonant media, are discussed with particular attention to the effect of transverse relaxation time T2. It is shown that the correlation trace (output light energy vs incident pulse separation) for this process provides a general means of obtaining information on ultrashort T2 for both the homogeneously and inhomogeneously broadened transitions, and for both tp(pulse width) <T2 and tp>T2. An experimental demonstration for tp> T2 is given by using a dye molecule and a picosecond light source. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.