Electronic structure and spin-filter effect of $\gamma$-Fe$_{2}$O$_{3}$ (maghemite)

ORAL

Abstract

We theoretically study the electronic structure and spin-dependent transport of spinel-like $\gamma$-Fe$_{2}$O$_{3}$ (maghemite) which is one of candidates for spin-filter devices. By performing first principles calculations (GGA+$U$) for iron vacancy ordered Fe$_{64}$O$_{96}$, the spin-dependent band-gap of the maghemite in the ferrimagnetic insulating ground state is determined. It is also shown that excess of Fe and O atoms significantly affects on the band gap of the minority spin state. In the light of obtained electronic structure, the spin-filter effect and variable range hopping of the maghemite are discussed.

–

Authors

  • Hiroyoshi Itoh

    • Department of Pure and Applied Physics, Kansai University, Japan

  • Syuta Honda

    • Department of Applied Physics, Nagoya University, Japan

  • Jun-ichiro Inoue

    • Department of Applied Physics, Nagoya University, Japan

  • Hideto Yanagihara

    • Institute of Applied Physics, University of Tsukuba, Japan

  • Eiji Kita

    • Institute of Applied Physics, University of Tsukuba, Japan