Ultrafast dynamics of VO$_2$ thin films measured in pump-probe configuration
ORAL
Abstract
The semiconductor-metal transition of VO$_2$ continues to be a vigorously studied phenomenon due to complicated interplay between the structural change and the electronic bands. It is also potentially a very useful material, particularly because of its ultrafast transition to the metallic state excited with a femtosecond pulse. We have been exploring the effects of polarization of the pump in relation to the probe affects the sub-picosecond response of VO$_2$ thin films, which will be important in designing ultrafast switches. We have also been looking at pumping our VO$_2$ films with a THz source that directly pumps the lattice, and have found the film responds optically on a slower scale than when pumped with 800 nm, suggesting that there is an electronic response from disturbing the lattice.
*This project was sponsored by the NSF, DMR-1006013: Plasmon Resonances and Metal Insulator Transitions in Highly Correlated Thin Film Systems, and the NASA Virginia Space Grant Consortium. We also acknowledge support from the NRI/SRC sponsored ViNC center
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