Comment on ‘‘Destructive Effect of Disorder and Bias Voltage on Interface Resonance Transmission in Symmetric Tunnel Junctions’’

Authors

Julian P. Velev, University of Nebraska-LincolnFollow
Kirill D. Belashchenko, University of Nebraska-LincolnFollow
Evgeny Y. Tsymbal, University of Nebraska-LincolnFollow

Date of this Version

3-24-2006

Comments

Published in PHYSICAL REVIEW LETTERS 96, 119601 (2006). © 2006 The American Physical Society. Used by permission.

Abstract

In a recent Letter Tusche et al. [1] showed that a complete and coherent FeO layer forms on both interfaces of a FejMgOjFe|001| magnetic tunnel junction (MTJ) when using oxygen-assisted growth. Their ab initio model for these MTJs predicted tunneling magnetoresistance (TMR) of several thousand percent due to the contribution from interface resonances (IRs) perfectly matched at the two interfaces. In this Comment, we show that in practice the predicted giant TMR is unfeasible because the IRs are mismatched by structural disorder and/or by applied bias voltage resulting in a moderate TMR.