Prediction of a spin-polarized two-dimensional electron gas at the ${\text{LaAlO}}_{3}/\text{EuO}(001)$ interface

Prediction of a spin-polarized two-dimensional electron gas at the ${LaAlO}_{3} / EuO (001)$ interface

Yong Wang, Manish K. Niranjan, J. D. Burton, Joonhee M. An, Kirill D. Belashchenko, and Evgeny Y. Tsymbal

Phys. Rev. B 79, 212408 – Published 23 June 2009

Abstract

First-principles calculations predict the existence of a spin-polarized two-dimensional electron gas (2DEG) at the LaO/EuO interface in a ${LaAlO}_{3} / EuO (001)$ heterostructure. This polar interface favors electron doping into the $Eu- 5 d$ conduction bands resulting in a 2DEG formed at the interface. Due to the exchange splitting of the $Eu- 5 d$ states, the 2DEG is spin polarized below the Curie temperature of EuO. The predicted mechanism for the formation of a spin-polarized 2DEG at the interface between polar and ferromagnetic insulators may provide a robust magnetism of the 2DEG which is interesting for spintronics applications.