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Title: Optimization of spin-torque switching using AC and DC pulses

Abstract

We explore spin-torque induced magnetic reversal in magnetic tunnel junctions using combined AC and DC spin-current pulses. We calculate the optimal pulse times and current strengths for both AC and DC pulses as well as the optimal AC signal frequency, needed to minimize the Joule heat lost during the switching process. The results of this optimization are compared against numeric simulations. Finally, we show how this optimization leads to different dynamic regimes, where switching is optimized by either a purely AC or DC spin-current, or a combination AC/DC spin-current, depending on the anisotropy energies and the spin-current polarization.

Authors:
 [1];  [1];  [2]
  1. Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
22304014
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 23; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANISOTROPY; CURRENTS; HEAT; OPTIMIZATION; P-N JUNCTIONS; POLARIZATION; PULSES; SIMULATION; SPIN; TORQUE; TUNNEL EFFECT

Citation Formats

Dunn, Tom, Kamenev, Alex, and Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455. Optimization of spin-torque switching using AC and DC pulses. United States: N. p., 2014. Web. doi:10.1063/1.4882757.
Dunn, Tom, Kamenev, Alex, & Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455. Optimization of spin-torque switching using AC and DC pulses. United States. doi:10.1063/1.4882757.
Dunn, Tom, Kamenev, Alex, and Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455. 2014. "Optimization of spin-torque switching using AC and DC pulses". United States. doi:10.1063/1.4882757.
@article{osti_22304014,
title = {Optimization of spin-torque switching using AC and DC pulses},
author = {Dunn, Tom and Kamenev, Alex and Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455},
abstractNote = {We explore spin-torque induced magnetic reversal in magnetic tunnel junctions using combined AC and DC spin-current pulses. We calculate the optimal pulse times and current strengths for both AC and DC pulses as well as the optimal AC signal frequency, needed to minimize the Joule heat lost during the switching process. The results of this optimization are compared against numeric simulations. Finally, we show how this optimization leads to different dynamic regimes, where switching is optimized by either a purely AC or DC spin-current, or a combination AC/DC spin-current, depending on the anisotropy energies and the spin-current polarization.},
doi = {10.1063/1.4882757},
journal = {Journal of Applied Physics},
number = 23,
volume = 115,
place = {United States},
year = 2014,
month = 6
}
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