UC Irvine

Time-resolved coherent anti-Stokes Raman scattering is applied to prepare and interrogate vibrational coherences on the ground electronic surface of molecular iodine isolated in Ar matrices. The coherence decay time shows a linear dependence on vibrational quantum numbers for v=3-15. The temperature dependence of decoherence rates is negligible for v<7 in the experimental range T=18-32 K. For a v=13, 14 superposition, the temperature dependence indicates dephasing by a 66 cm(-1) pseudo-local phonon, just outside the Debye edge of the solid. The accuracy of the data is limited due to two-photon induced dissociation of the molecule, a process which is characterized using polarized fields. The T-->0 limit of dephasing is discussed. (C) 2003 American Institute of Physics.