Date Awarded
Fall 2016
Document Type
Dissertation
Degree Name
Doctor of Philosophy (Ph.D.)
Department
Physics
Advisor
Irina Novikova
Committee Member
Rosa A. Lukaszew
Committee Member
Enrico Rossi
Committee Member
Mumtaz Qazilbash
Committee Member
Russell A. Wincheski
Abstract
Vanadium dioxide is an intensely studied material, since it goes through an insulator-metal transition at a critical temperature just above room temperature at 340~K. The dramatic change in conductivity and the easily accessible transition temperature makes it an attractive material for novel technologies. Thin films of VO2 have a reversible transition without any significant degradation in contrast, and depending on the microstructure of the films, the properties of the transition are tunable. In this work, I study the dynamics of the insulator-transition in thin films grown on different substrates using a pump-probe configuration. The energy needed to trigger the transition, as well as the time constants of the change in reflectivity are affected by the strain in the VO2 films. I also characterized the samples using Raman spectroscopy and XRD measurements in order to identify what underlies the differences in behavior. Finally, in collaboration with Dr. Yamaguchi's group at RPI, I show that it is possible to trigger the transition using a THz pulse that directly pumps energy into the lattice, and at lower energies than needed to pump films by photoinducing the electrons across the band gap.
DOI
http://doi.org/10.21220/S24K52
Rights
© The Author
Recommended Citation
Radue, Elizabeth Lee, "Study of Variations of the Dynamics of the Metal-Insulator Transition of Thin Films of Vanadium Dioxide with An Ultra-Fast Laser" (2016). Dissertations, Theses, and Masters Projects. William & Mary. Paper 1477068473.
http://doi.org/10.21220/S24K52
