Digital Tuning of the Transition Temperature of Epitaxial VO2 Thin Films on MgF2 Substrates by Strain Engineering
Abstract
Straining the vanadium dimers along the rutile c‐axis can be used to tune the metal‐to‐insulator transition (MIT) of VO2 but has thus far been limited to TiO2 substrates. In this work VO2/MgF2 epitaxial films are grown via molecular beam epitaxy (MBE) to strain engineer the transition temperature (TMIT). First, growth parameters are optimized by varying the synthesis temperature of the MgF2 (001) substrate (TS) using a combination of X‐ray diffraction techniques, temperature dependent transport, and soft X‐ray photoelectron spectroscopy. It is determined that TS values greater than 350 °C induce Mg and F interdiffusion and ultimately the relaxation of the VO2 layer. Using the optimized growth temperature, VO2/MgF2 (101) and (110) films are then synthesized. The three film orientations display MITs with transition temperatures in the range of 15–60 °C through precise strain engineering.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 09, 2021
- Source ID
- 10.1002/admi.202001790
Entities
People
- Darrell G. Schlom
- Egor Evlyukhin
- Galo J Paez
- Hanjong Paik
- Louis F. J. Piper
- Sebastian A Howard
Organizations
- Air Force Office of Scientific Research
- Binghamton University
- Cornell University
- National Science Foundation
- Office of Science
- University of Warwick