Time-resolved coherent anti-Stokes Raman-scattering measurements of I2 in solid Kr:: Vibrational dephasing on the ground electronic state at 2.6-32 K -: art. no. 064509

Time-resolved coherent anti-Stokes Raman-scattering (CARS) measurements are carried out for iodine (I-2) in solid krypton matrices. The dependence of vibrational dephasing time on temperature and vibrational quantum number v is studied. The v dependence is approximately quadratic, while the temperature dependence of both vibrational dephasing and spectral shift, although weak, fits the exponential form characteristic of dephasing by pseudolocal phonons. The analysis of the data indicates that the frequency of the pseudolocal phonons is similar to 30 cm(-1). The longest dephasing times are observed for v=2 being similar to 300 ps and limited by inhomogeneous broadening. An increase in the dephasing rate of v=2 as the temperature is lowered to T=2.6 K is taken as a clear indication of lattice-strain-induced inhomogeneity of the ensemble coherence. (C) 2005 American Institute of Physics.