Backhopping effect in magnetic tunnel junctions: Comparison between theory and experiment
W. Skowroński , Piotr Ogrodnik , J. Wrona , T. Stobiecki , Renata Świrkowicz , J. Barnaś , G. Reiss , S. Van Dijken
AbstractWe report on magnetic switching and backhopping effects due to spin-transfer-torque in magnetic tunnel junctions. Experimental data on current-induced switching in junctions with a MgO tunnel barrier reveal random back-and-forth switching between magnetization states, which appears when the current direction favors the parallel magnetic configuration. The effect depends on the barrier thickness tb and is not observed in tunnel junctions with very thin MgO tunnel barriers, tb < 0.95 nm. The switching dependence on bias voltage and barrier thickness is explained in terms of the macrospin model, with the magnetization dynamics described by the modified Landau-Lifshitz-Gilbert equation. Numerical simulations indicate that the competition between in-plane and out-of-plane torque components can result in a non-deterministic switching behavior at high bias voltages, in agreement with experimental observations. When the barrier thickness is reduced, the overall coupling between the magnetic layers across the barrier becomes ferromagnetic, which suppresses the backhopping effect. © 2013 AIP Publishing LLC.
|Journal series||Journal of Applied Physics, ISSN 0021-8979|
|Score|| = 35.0, 01-01-2020, ArticleFromJournal|
= 35.0, 01-01-2020, ArticleFromJournal
|Publication indicators||= 5; : 2013 = 1.289; : 2013 = 2.185 (2) - 2013=2.259 (5)|
|Citation count*||1 (2015-02-04)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.