Ferromagnetism in Rutile Structure Cr doped VO$_{2}$ Thin Films prepared by Reactive Bias Target Ion Beam Deposition

ORAL

Abstract

First generation spintronics has entered the mainstream of information technology through its utilization of the Magnetic Tunnel Junction (MTJ) in applicable devices such as read head sensors for hard disk drives and Magnetic Random Access Memory (MRAM). The future of spintronic devices requires next generation spintronic materials. Here we report on the novel structural, transport, and magnetic characteristics of V$_{1-x}$Cr$_{x}$O$_{2}$ (0.1 $\le $ x $\le $ 0.2) thin films deposited on (001) Al$_{2}$O$_{3}$ substrates. We show that the metal-insulator transition (MIT) of VO$_{2}$ is suppressed and the rutile structure is stable down to 100 K. The films are remarkably smooth having a root-mean squared (RMS) surface roughness of 0.3 nm. Films are conductive at room temperature and appear to follow a variable-range-hopping conduction mechanism below that. Ferromagnetism is observed at room temperature and is dependent on Cr concentration. The combination of these characteristics makes V$_{1-x}$Cr$_{x}$O$_{2}$ a viable candidate material for next generation spintronic multilayer devices.

Authors

  • Kevin West

    University of Virginia

  • Jiwei Lu

    University of Virginia

  • Li He

    University of Virginia

  • David Kirkwood

    University of Virginia

  • Wei Chen

    University of Virginia

  • T. Paul Adl

    Micron Technology

  • Michael S. Osofsky

    US. Naval Research Labs

  • Syed B. Qadri

    US. Naval Research Labs

  • Robert Hull

    University of Virginia

  • Stuart Wolf

    University of Virginia