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

Journal Article · Mon Jul 18 00:00:00 EDT 2016 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4958833· OSTI ID:22594470

Bose, Arnab; Jain, Sourabh; Asam, Nagarjuna; Bhuktare, Swapnil; Singh, Hanuman; Tulapurkar, Ashwin A. ^[1]; Shukla, Amit Kumar; Konishi, Katsunori; Lam, Duc Duong; Fujii, Yuya; Miwa, Shinji; Suzuki, Yoshishige ^[2]

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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)

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.

• OSTI ID: 22594470
• Journal Information: Applied Physics Letters, Vol. 109, Issue 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

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