Summary: Z .Chemical Physics 233 1998 353­363
Wavepacket diagnosis with chirped probe pulses
R. Zadoyan )
, N. Schwentner 1
, V.A. Apkarian
Department of Chemistry, UniÕersity of California, IrÕine, CA 92697, USA
Received 29 January 1998
Abstract
For linearly chirped probe pulses, the observable pump­probe signal can be obtained analytically under useful
idealizations: Gaussian packet and pulse, linear chirp, linear difference potential, and constant wavepacket group velocity
within the probe window. These conditions allow the expression of the signal as a cross correlation between packet and
probe window traveling in coordinate space at velocities Õ and Õ , respectively. The signal delay and its integrated area arel
independent of chirp. Relative to zero-chirp, the signal is temporally compressed for 0-ÕrÕ -2, and becomes a minimuml
when packet and window co-propagate, ÕsÕ . Experimental data are used to illustrate wavepacket diagnosis in a reall
system. q 1998 Elsevier Science B.V. All rights reserved.
Keywords: Wavepacket diagnosis; Chirped probe pulses; Probes
1. Introduction
Time resolved measurements in the ultrafast domain necessarily involve two pulses: a pump-pulse, which
prepares an initial nonstationary superposition state, or a wavepacket; and a probe-pulse, which interrogates the
w xpacket after some time evolution. Many theoretical models, ranging from classical 1,2 , to generalized linear

Source: Apkarian, V. Ara - Department of Chemistry, University of California, Irvine

Collections: Chemistry