Fabrication and magnetotransport properties of high mobility EuTiO<sub>3</sub> quantum wells

ORAL

Abstract

EuTiO3 (ETO) is a magnetic semiconductor with an antiferromagnetically ordering at 5.5 K for the 4f7 moments on Eu2+ site. Electron carriers can be doped into Ti t2g conduction band by substituting Eu2+ by La3+. We previously reported a peculiar behavior of anomalous Hall effect (AHE) of compressively strained La doped EuTiO3 (Eu1-xLaxTiO3) films on LSAT substrates grown by pulsed laser deposition (PLD).
In this work, we fabricated Eu1-xLaxTiO3 films on SrTiO3 (STO) substrates by metal organic gas source molecular beam epitaxy (MOMBE) at very high substrate temperature (1200 °C). It is expected that there is no epitaxial strain due to the identical lattice constants of ETO and STO. By optimizing the annealing conditions, we succeeded in compensating the oxygen vacancies and in investigating the transport properties of the films. The mobility of electrons is two orders of magnitude higher than that of PLD films and the maximum value reaches 3000 cm2V-1s-1 at 2 K. We clearly observed Shubnikov-de Haas oscillations in magnetoresistance and non-monotonic behavior of AHE. Our results will provide unique insights into the quantum transport of low carrier density electrons with spin polarization.

–

Presenters

  • Kazuki Maruhashi

    • Department of Applied Physics, The University of Tokyo

Authors

  • Kazuki Maruhashi

    • Department of Applied Physics, The University of Tokyo

  • Kei Takahashi

    • RIKEN
    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN Center for Emergent Matter Science
    • CEMS, RIKEN
    • Center for Emergent Matter Science (CEMS), RIKEN

  • Yoshinori Tokura

    • RIKEN Center for Emergent Matter Science (CEMS)
    • CEMS, RIKEN
    • RIKEN
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • RIKEN Center for Emergent Matter Science
    • Center for Emergent Matter Science (CEMS), RIKEN
    • Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo

  • Masashi Kawasaki

    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), the University of Tokyo
    • Univ of Tokyo
    • The University of Tokyo
    • Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo
    • Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), Univ. of Tokyo
    • Applied Physics, University of Tokyo
    • Department of Applied Physics, The University of Tokyo
    • Department of Applied Physics, University of Tokyo