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Title: Role of spin-transfer torques on synchronization and resonance phenomena in stochastic magnetic oscillators

Abstract

A theoretical study on how synchronization and resonance-like phenomena in superparamagnetic tunnel junctions can be driven by spin-transfer torques is presented. We examine the magnetization of a superparamagnetic free layer that reverses randomly between two well-defined orientations due to thermal fluctuations, acting as a stochastic oscillator. When subject to an external ac forcing, this system can present stochastic resonance and noise-enhanced synchronization. We focus on the roles of the mutually perpendicular damping-like and field-like torques, showing that the response of the system is very different at low and high frequencies. We also demonstrate that the field-like torque can increase the efficiency of the current-driven forcing, especially at sub-threshold electric currents. These results can be useful for possible low-power, more energy efficient applications.

Authors:
 [1];  [2]; ; ;  [3];  [3];  [2];  [1];  [4]
  1. Instituto de Física, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre (Brazil)
  2. (France)
  3. Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay (France)
  4. Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, F91767 Palaiseau (France)
Publication Date:
OSTI Identifier:
22598807
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DAMPING; EFFICIENCY; ELECTRIC CURRENTS; FLUCTUATIONS; LAYERS; MAGNETIZATION; NOISE; OSCILLATORS; RESONANCE; SPIN; STOCHASTIC PROCESSES; SUPERPARAMAGNETISM; SYNCHRONIZATION; TORQUE

Citation Formats

Accioly, Artur, Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay, Locatelli, Nicolas, Querlioz, Damien, Kim, Joo-Von, Mizrahi, Alice, Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, F91767 Palaiseau, Pereira, Luis G., and Grollier, Julie. Role of spin-transfer torques on synchronization and resonance phenomena in stochastic magnetic oscillators. United States: N. p., 2016. Web. doi:10.1063/1.4962015.
Accioly, Artur, Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay, Locatelli, Nicolas, Querlioz, Damien, Kim, Joo-Von, Mizrahi, Alice, Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, F91767 Palaiseau, Pereira, Luis G., & Grollier, Julie. Role of spin-transfer torques on synchronization and resonance phenomena in stochastic magnetic oscillators. United States. doi:10.1063/1.4962015.
Accioly, Artur, Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay, Locatelli, Nicolas, Querlioz, Damien, Kim, Joo-Von, Mizrahi, Alice, Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, F91767 Palaiseau, Pereira, Luis G., and Grollier, Julie. Wed . "Role of spin-transfer torques on synchronization and resonance phenomena in stochastic magnetic oscillators". United States. doi:10.1063/1.4962015.
@article{osti_22598807,
title = {Role of spin-transfer torques on synchronization and resonance phenomena in stochastic magnetic oscillators},
author = {Accioly, Artur and Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay and Locatelli, Nicolas and Querlioz, Damien and Kim, Joo-Von and Mizrahi, Alice and Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, F91767 Palaiseau and Pereira, Luis G. and Grollier, Julie},
abstractNote = {A theoretical study on how synchronization and resonance-like phenomena in superparamagnetic tunnel junctions can be driven by spin-transfer torques is presented. We examine the magnetization of a superparamagnetic free layer that reverses randomly between two well-defined orientations due to thermal fluctuations, acting as a stochastic oscillator. When subject to an external ac forcing, this system can present stochastic resonance and noise-enhanced synchronization. We focus on the roles of the mutually perpendicular damping-like and field-like torques, showing that the response of the system is very different at low and high frequencies. We also demonstrate that the field-like torque can increase the efficiency of the current-driven forcing, especially at sub-threshold electric currents. These results can be useful for possible low-power, more energy efficient applications.},
doi = {10.1063/1.4962015},
journal = {Journal of Applied Physics},
number = 9,
volume = 120,
place = {United States},
year = {Wed Sep 07 00:00:00 EDT 2016},
month = {Wed Sep 07 00:00:00 EDT 2016}
}
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