Electric Control of Spin Injection into a Ferroelectric Semiconductor

Authors

Xiaohui Liu, University of Nebraska-LincolnFollow
John D. Burton, University of Nebraska-LincolnFollow
M. Ye. Zhuravlev, Kurnakov Institute for General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
Evgeny Y. Tsymbal, University of Nebraska-LincolnFollow

Date of this Version

1-29-2015

Citation

PHYSICAL REVIEW LETTERS 114, 046601 (2015). DOI: 10.1103/PhysRevLett.114.046601

Comments

Copyright 2015 American Physical Society. Used by permission.

Abstract

Electric-field control of spin-dependent properties has become one of the most attractive phenomena in modern materials research due to the promise of new device functionalities. One of the paradigms in this approach is to electrically toggle the spin polarization of carriers injected into a semiconductor using ferroelectric polarization as a control parameter. Using first-principles density-functional calculations, we explore the effect of ferroelectric polarization of electron-doped BaTiO₃ (n-BaTiO₃) on the spin-polarized transmission across the SrRuO₃/n-BaTiO₃(001) interface. Our study reveals that, in this system, the interface transmission is negatively spin polarized and that ferroelectric polarization reversal leads to a change in the transport spin polarization from −65% to −98%. Analytical model calculations demonstrate that this is a general effect for ferromagnetic-metal–ferroelectric-semiconductor systems and, furthermore, that ferroelectric modulation can even reverse the sign of spin polarization. The predicted effect provides a nonvolatile mechanism to electrically control spin injection in semiconductor-based spintronics devices.