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arXiv · 1904.09341

Sub-terahertz ferrimagnetic spin-transfer torque oscillator

Ivan Lisenkov·Roman Khymyn·Johan Akerman·Nian X. Sun·Boris A. Ivanov
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Abstract

A theory of magnetization dynamics in ferrimagnetic materials with antiparallel aligned spin sub-lattices under action of spin-transfer torques (STT) is developed. We consider magnetization dynamics in GdFeCo layers in two cases of magnetic anisotropy: easy plane and easy axis. We demonstrate that, (i) for the easy plane anisotropy the precession of the N\'{e}el vector is conical and the cone angle depends on the STT strength and the value of spin non-compensation, while the frequency of precession can reach sub-THz frequencies; (ii) for the easy axis anisotropy two regimes are possible: deterministic switching of the net magnetization and a conical sub-THz precession depending on the STT strength.

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Ivan Lisenkov, Roman Khymyn, Johan Akerman, Nian X. Sun, Boris A. Ivanov. 2019-04-19. Sub-terahertz ferrimagnetic spin-transfer torque oscillator. https://doi.org/10.1103/physrevb.100.100409

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