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Title: Observation of thermally driven field-like spin torque in magnetic tunnel junctions

Abstract

We report the thermally driven giant field-like spin-torque in magnetic tunnel junctions (MTJ) on application of heat current from top to bottom. The field-like term is detected by the shift of the magneto-resistance hysteresis loop applying temperature gradient. We observed that the field-like term depends on the magnetic symmetry of the MTJ. In asymmetric structures, with different ferromagnetic materials for free and fixed layers, the field-like term is greatly enhanced. Our results show that a pure spin current density of the order of 10{sup 9 }A/m{sup 2} can be produced by creating a 120 mK temperature difference across 0.9 nm thick MgO tunnelling barrier. Our results will be useful for writing MTJ and domain wall-based memories using thermally driven spin torque.

Authors:
; ; ; ; ;  [1]; ; ; ; ; ;  [2]
  1. Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai 400076 (India)
  2. Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)
Publication Date:
OSTI Identifier:
22594470
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 3; 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; ASYMMETRY; CURRENT DENSITY; FERROMAGNETIC MATERIALS; HEAT; HYSTERESIS; LAYERS; MAGNESIUM OXIDES; MAGNETIC TUNNEL JUNCTIONS; MAGNETORESISTANCE; SPIN; SYMMETRY; TEMPERATURE GRADIENTS; TORQUE; TUNNEL EFFECT; WALLS

Citation Formats

Bose, Arnab, E-mail: arnabbose@ee.iitb.ac.in, Jain, Sourabh, Asam, Nagarjuna, Bhuktare, Swapnil, Singh, Hanuman, Tulapurkar, Ashwin A., Shukla, Amit Kumar, Konishi, Katsunori, Lam, Duc Duong, Fujii, Yuya, Miwa, Shinji, and Suzuki, Yoshishige. Observation of thermally driven field-like spin torque in magnetic tunnel junctions. United States: N. p., 2016. Web. doi:10.1063/1.4958833.
Bose, Arnab, E-mail: arnabbose@ee.iitb.ac.in, Jain, Sourabh, Asam, Nagarjuna, Bhuktare, Swapnil, Singh, Hanuman, Tulapurkar, Ashwin A., Shukla, Amit Kumar, Konishi, Katsunori, Lam, Duc Duong, Fujii, Yuya, Miwa, Shinji, & Suzuki, Yoshishige. Observation of thermally driven field-like spin torque in magnetic tunnel junctions. United States. doi:10.1063/1.4958833.
Bose, Arnab, E-mail: arnabbose@ee.iitb.ac.in, Jain, Sourabh, Asam, Nagarjuna, Bhuktare, Swapnil, Singh, Hanuman, Tulapurkar, Ashwin A., Shukla, Amit Kumar, Konishi, Katsunori, Lam, Duc Duong, Fujii, Yuya, Miwa, Shinji, and Suzuki, Yoshishige. 2016. "Observation of thermally driven field-like spin torque in magnetic tunnel junctions". United States. doi:10.1063/1.4958833.
@article{osti_22594470,
title = {Observation of thermally driven field-like spin torque in magnetic tunnel junctions},
author = {Bose, Arnab, E-mail: arnabbose@ee.iitb.ac.in and Jain, Sourabh and Asam, Nagarjuna and Bhuktare, Swapnil and Singh, Hanuman and Tulapurkar, Ashwin A. and Shukla, Amit Kumar and Konishi, Katsunori and Lam, Duc Duong and Fujii, Yuya and Miwa, Shinji and Suzuki, Yoshishige},
abstractNote = {We report the thermally driven giant field-like spin-torque in magnetic tunnel junctions (MTJ) on application of heat current from top to bottom. The field-like term is detected by the shift of the magneto-resistance hysteresis loop applying temperature gradient. We observed that the field-like term depends on the magnetic symmetry of the MTJ. In asymmetric structures, with different ferromagnetic materials for free and fixed layers, the field-like term is greatly enhanced. Our results show that a pure spin current density of the order of 10{sup 9 }A/m{sup 2} can be produced by creating a 120 mK temperature difference across 0.9 nm thick MgO tunnelling barrier. Our results will be useful for writing MTJ and domain wall-based memories using thermally driven spin torque.},
doi = {10.1063/1.4958833},
journal = {Applied Physics Letters},
number = 3,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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