A joint project of the Graduate School, Peabody College, and the Jean & Alexander Heard Library

Title page for ETD etd-04202011-182358


Type of Document Dissertation
Author Nag, Joyeeta
Author's Email Address joyeeta.nag@Vanderbilt.Edu
URN etd-04202011-182358
Title The solid-solid phase transition in vanadium dioxide thin films: synthesis, physics and application
Degree PhD
Department Physics
Advisory Committee
Advisor Name Title
Prof. Richard F. Haglund, Jr. Committee Chair
Prof. Akunuri V. Ramayya Committee Member
Prof. Leonard C. Feldman Committee Member
Prof. Sharon M. Weiss Committee Member
Prof. Sokrates T. Pantelides Committee Member
Keywords
  • optical modulator
  • doping
  • thin films
  • epitaxy
  • vanadium dioxide
  • phase transition
  • metal-insulator transition
  • hybrid modulator
  • ring resonator
Date of Defense 2011-03-25
Availability unrestricted
Abstract
THE SOLID-SOLID PHASE TRANSITION IN VANADIUM DIOXIDE THIN FILMS: SYNTHESIS, PHYSICS AND APPLICATION

JOYEETA NAG

DISSERTATION UNDER THE DIRECTION OF PROFESSOR RICHARD F. HAGLUND, JR.

This dissertation is devoted to the impact of materials physics and materials synthesis on the characteristics of the solid-solid phase transition in vanadium dioxide thin films. In vanadium dioxide, the solid-solid phase transition comprises both an insulator-to-metal transition and a monoclinic-to-tetragonal structural transformation. The morphology, transition characteristics and energy cost of the phase transition in this strongly correlated material are shown to be strongly dependent on the details of the synthesis process. It was discovered that the conventional protocol for preparing epitaxial films on c-sapphire produces nanoparticulate samples, whereas room temperature deposition followed by annealing tends to produce remarkably smooth films, which are substantially better-suited for applications. For epitaxial VO2 films grown on c-sapphire, using both the above-mentioned protocols, it was found that the thermally-induced structural and metal-insulator transitions are not congruent due to the larger energy cost of the former. The energy of the phase transformation can be modified by doping with tungsten, and both the thermally induced transition and the ultrafast laser-induced switching between insulating and metallic states show evidence of this. The novel properties of the phase transition inVO2 thin films finds a compelling application in the modulation of a hybrid Si:VO2 ring resonator, a basic building block of photonic logic circuits.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Dissertation_Joyeeta.pdf 11.26 Mb 00:52:08 00:26:49 00:23:27 00:11:43 00:01:00

Browse All Available ETDs by ( Author | Department )

If you have more questions or technical problems, please Contact LITS.