Enhanced Photosusceptibility near Tc for the Light-Induced Insulator-to-Metal Phase Transition in Vanadium Dioxide

DOI: 10.1103/PhysRevLett.99.226401
PMID: 18233305

Authors: D. J. Hilton (Center for Integrated Nanotechnologies, Los Alamos National Laboratory, New Mexico) , R. P. Prasankumar (Center for Integrated Nanotechnologies, Los Alamos National Laboratory, New Mexico) , S. Fourmaux (Université du Québec, Canada) , A. Cavalleri (University of Oxford) , D. Brassard (Université du Québec, Canada) , M. A. El Khakani (Université du Québec, Canada) , J. C. Kieffer (Université du Québec, Canada) , A. J. Taylor (Center for Integrated Nanotechnologies, Los Alamos National Laboratory, New Mexico) , R. D. Averitt (Center for Integrated Nanotechnologies, Los Alamos National Laboratory, New Mexico)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review Letters , VOL 99 (22)

State: Published (Approved)
Published: November 2007

Abstract: We use optical-pump terahertz-probe spectroscopy to investigate the near-threshold behavior of the photoinduced insulator-to-metal (IM) transition in vanadium dioxide thin films. Upon approaching Tc a reduction in the fluence required to drive the IM transition is observed, consistent with a softening of the insulating state due to an increasing metallic volume fraction (below the percolation limit). This phase coexistence facilitates the growth of a homogeneous metallic conducting phase following superheating via photoexcitation. A simple dynamic model using Bruggeman effective medium theory describes the observed initial condition sensitivity.

Subject Areas: Physics


Technical Areas: