Ultrafast Excited-State Dynamics of V_{3}O_{5} as a Signature of a Photoinduced Insulator-Metal Phase Transition.

The ultrafast elastic light scattering technique is applied to reveal the strong nonlinearity of V_{3}O_{5} associated with a photoinduced insulator-metal phase transition. Observation of time-domain relaxation dynamics suggests several stages of structural transition. We discuss the nonequilibrium processes in V_{3}O_{5} in terms of photoinduced melting of a polaronic Wigner crystal, coalescence of V-O octahedra, and photogeneration of acoustical phonons in the low-T and high-T phases of V_{3}O_{5}. A molecular dynamics computation supports experimentally observed stages of V_{3}O_{5} relaxation dynamics.