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Title: Diameter dependence of emission power in MgO-based nano-pillar spin-torque oscillators

Abstract

The dependence on diameter of the emission power in MgO-based nano-pillar spin torque oscillators (STOs) was systematically investigated. A maximum emission power of over 2.5 μW was obtained around 300 nm in diameter, which is the largest reported to date among the out-of-plane precession STOs. By analyzing physical quantities, precession cone angle of the free-layer magnetization was evaluated. In the diameter range below 300 nm, the increase in power was mainly due to the increase of the injected current. The power decrease above 300 nm is possibly attributed to the decrease in the averaged precession cone angle, suggesting spatial phase difference of magnetization precession. This study provides the method for estimating the optimum STO diameter, which is of great importance in practical use.

Authors:
; ; ; ; ; ; ;  [1]
  1. Spintronics Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan)
Publication Date:
OSTI Identifier:
22590830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 25; 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; CURRENTS; EMISSION; LAYERS; MAGNESIUM OXIDES; MAGNETIZATION; OSCILLATORS; PRECESSION; SPIN; TORQUE

Citation Formats

Wang, Bochong, Kubota, Hitoshi, E-mail: hit-kubota@aist.go.jp, Yakushiji, Kay, Tamaru, Shingo, Arai, Hiroko, Imamura, Hiroshi, Fukushima, Akio, and Yuasa, Shinji. Diameter dependence of emission power in MgO-based nano-pillar spin-torque oscillators. United States: N. p., 2016. Web. doi:10.1063/1.4954760.
Wang, Bochong, Kubota, Hitoshi, E-mail: hit-kubota@aist.go.jp, Yakushiji, Kay, Tamaru, Shingo, Arai, Hiroko, Imamura, Hiroshi, Fukushima, Akio, & Yuasa, Shinji. Diameter dependence of emission power in MgO-based nano-pillar spin-torque oscillators. United States. doi:10.1063/1.4954760.
Wang, Bochong, Kubota, Hitoshi, E-mail: hit-kubota@aist.go.jp, Yakushiji, Kay, Tamaru, Shingo, Arai, Hiroko, Imamura, Hiroshi, Fukushima, Akio, and Yuasa, Shinji. 2016. "Diameter dependence of emission power in MgO-based nano-pillar spin-torque oscillators". United States. doi:10.1063/1.4954760.
@article{osti_22590830,
title = {Diameter dependence of emission power in MgO-based nano-pillar spin-torque oscillators},
author = {Wang, Bochong and Kubota, Hitoshi, E-mail: hit-kubota@aist.go.jp and Yakushiji, Kay and Tamaru, Shingo and Arai, Hiroko and Imamura, Hiroshi and Fukushima, Akio and Yuasa, Shinji},
abstractNote = {The dependence on diameter of the emission power in MgO-based nano-pillar spin torque oscillators (STOs) was systematically investigated. A maximum emission power of over 2.5 μW was obtained around 300 nm in diameter, which is the largest reported to date among the out-of-plane precession STOs. By analyzing physical quantities, precession cone angle of the free-layer magnetization was evaluated. In the diameter range below 300 nm, the increase in power was mainly due to the increase of the injected current. The power decrease above 300 nm is possibly attributed to the decrease in the averaged precession cone angle, suggesting spatial phase difference of magnetization precession. This study provides the method for estimating the optimum STO diameter, which is of great importance in practical use.},
doi = {10.1063/1.4954760},
journal = {Applied Physics Letters},
number = 25,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
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