Article

Femtosecond Structural Dynamics in VO 2 during an Ultrafast Solid-Solid Phase Transition

University of California San Diego, La Jolla, California 92093-0339, USA.
Physical Review Letters (Impact Factor: 7.73). 01/2002; 87(23):237401. DOI: 10.1103/PhysRevLett.87.237401
Source: PubMed

ABSTRACT Femtosecond x-ray and visible pulses were used to probe structural and electronic dynamics during an optically driven, solid-solid phase transition in ${\mathrm{VO}}_{2}$. For high interband electronic excitation $($\sim${}5\ifmmode\times\else\texttimes\fi{}{10}^{21}{\mathrm{cm}}^{$-${}3})$, a subpicosecond transformation into the high- $T$, rutile phase of the material is observed, simultaneous with an insulator-to-metal transition. The fast time scale observed suggests that, in this regime, the structural transition may not be thermally initiated.

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