Spin-transfer-torque-induced zero-field microwave oscillator using a magnetic easy cone state

Peong Hwa Jang, Seo Won Lee, Kyoung Jin Lee

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Current-induced spin-transfer torque can induce magnetization precession in gigahertz ranges, which enables various microwave devices. In most cases, this current-induced precession requires an additional external magnetic field, which is detrimental for device applications. In this work, we show that the current-induced precession is realized even without an external field when the magnetic layer has conical magnetization, caused by the second order easy-axis magnetic anisotropy. We theoretically derive the oscillation frequency and output power and confirm their validity by macrospin simulations. We find that the ratio of the second to the first anisotropy constants is key to determine the maximum frequency and power. Our results will be helpful for the applications of microwave devices utilizing spin-transfer torques and provide a design rule of such devices.

Original languageEnglish
Pages (from-to)1550-1553
Number of pages4
JournalCurrent Applied Physics
Volume16
Issue number12
DOIs
Publication statusPublished - 2016 Dec 1

Fingerprint

Microwave oscillators
microwave oscillators
Induced currents
torque
Cones
Microwave devices
cones
Torque
precession
Magnetization
Magnetic anisotropy
microwaves
magnetization
anisotropy
Anisotropy
Magnetic fields
oscillations
output
magnetic fields
simulation

Keywords

  • Spin-torque oscillator
  • Spin-transfer torque

ASJC Scopus subject areas

  • Materials Science(all)
  • Physics and Astronomy(all)

Cite this

Spin-transfer-torque-induced zero-field microwave oscillator using a magnetic easy cone state. / Jang, Peong Hwa; Lee, Seo Won; Lee, Kyoung Jin.

In: Current Applied Physics, Vol. 16, No. 12, 01.12.2016, p. 1550-1553.

Research output: Contribution to journalArticle

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