Tracking the insulator-to-metal phase transition in VO 2 with few-femtosecond extreme UV transient absorption spectroscopy
Abstract
An insulator-to-metal phase transition is a process that changes a solid material from being electrically nonconductive to being conductive. The phase transition in vanadium dioxide is a well-studied example where the process can occur in less than a picosecond, making it exciting for ultrafast electronic switches. This paper measures a record speed for the phase transition of 26 fs into a long-lived excited state of the metal that persists out to >60 ps. The extreme UV absorption spectrum of the material is also measured and (together with the ultrafast timescale) belies a structural mechanism that has long been deliberated. The measured femtosecond timescale provides fundamental insight into the electronic speed limits of these complex phenomena.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 21, 2017
- Source ID
- 10.1073/pnas.1707602114
Entities
People
- Christian Ott
- Christopher J. Kaplan
- Daniel Neumark
- Marieke F. Jager
- Peter M. Kraus
- Richard F. Haglund
- Robert E. Marvel
- Stephen R. Leone
- Winston Pouse
Organizations
- Air Force Office of Scientific Research
- Lawrence Berkeley National Laboratory
- National Science Foundation
- Vanderbilt University
- W. M. Keck Foundation
- Yusuf Hamied Department of Chemistry