Resonant Tunneling across a Ferroelectric Domain Wall

Authors

• M. Li, University of Nebraska - LincolnFollow
• L. L. Tao, University of Nebraska - LincolnFollow
• J. P. Velev, University of Puerto Rico, San JuanFollow
• Evgeny Y. Tsymbal, University of Nebraska-LincolnFollow

ORCID IDs

Tsymbal http://orcid.org/0000-0002-6728-5553

Document Type

Article

Date of this Version

4-10-2018

Citation

Physical Review B (2018) 97: 155121 (2018).

doi: 10.1103/PhysRevB.97.155121

Comments

Copyright 2018, American Physical Society. Used by permission

Abstract

Motivated by recent experimental observations, we explore electron transport properties of a ferroelectric tunnel junction (FTJ) with an embedded head-to-head ferroelectric domain wall, using first-principles density-functional theory calculations. We consider a FTJ with La_0.5Sr_0.5MnO₃ electrodes separated by a BaTiO₃ barrier layer and show that an in-plane charged domain wall in the ferroelectric BaTiO₃ can be induced by polar interfaces. The resulting V-shaped electrostatic potential profile across the BaTiO₃ layer creates a quantum well and leads to the formation of a two-dimensional electron gas, which stabilizes the domain wall. The confined electronic states in the barrier are responsible for resonant tunneling as is evident from our quantum-transport calculations. We find that the resonant tunneling is an orbital selective process, which leads to sharp spikes in the momentum- and energy-resolved transmission spectra. Our results indicate that domain walls embedded in FTJs can be used to control the electron transport.