Two‐Dimensional Mott Insulators in SrVO3 Ultrathin Films

Abstract

Strongly correlated oxides that undergo a metal‐insulator transition (MIT) are a subject of great current interest for their potential application to future electronics as switches and sensors. Recent advances in thin film technology have opened up new avenues to tailor MIT for novel devices beyond conventional CMOS scaling. Here, dimensional‐crossover‐driven MITs are demonstrated in high‐quality epitaxial SrVO3 (SVO) thin films grown by a pulsed electron‐beam deposition technique. Thick SVO films (∼25 nm) exhibit metallic behavior with the electrical resistivity following the T2 law corresponding to a Fermi liquid system. A temperature driven MIT is induced in SVO ultrathin films with thicknesses below 6.5 nm. The transition temperature TMIT is at 50 K for the 6.5 nm film, 120 K for the 5.7 nm film and 205 K for the 3 nm film. The emergence of the observed MIT can be attributed to the dimensional crossover from a three‐dimensional metal to a two‐dimensional Mott insulator, as the resulting reduction in the effective bandwidth W opens a band gap at the Fermi level. The magneto‐transport study of the SVO ultrathin films also confirm the observed MIT is due to the electron‐electron interactions other than disorder‐induced localization.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 06, 2014
Source ID
10.1002/admi.201300126

Entities

People

  • Jiwei Lu
  • Man Gu
  • Stuart A. Wolf

Organizations

  • Army Research Office
  • University of Virginia

Tags

Fields of Study

  • Physics

Readers

  • Aerospace Research.
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.
  • Thin Film Deposition Science.

Technology Areas

  • Directed Energy
  • Directed Energy - Pulsed-Laser Deposition
  • Microelectronics
  • Microelectronics - Graphene