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Ultrafast spin dynamics and switching via spin transfer torque in antiferromagnets with weak ferromagnetism.

ABSTRACT: The spin-torque driven dynamics of antiferromagnets with Dzyaloshinskii-Moriya interaction (DMI) were investigated based on the Landau-Lifshitz-Gilbert-Slonczewski equation with antiferromagnetic and ferromagnetic order parameters (l and m, respectively). We demonstrate that antiferromagnets including DMI can be described by a 2-dimensional pendulum model of l. Because m is coupled with l, together with DMI and exchange energy, close examination of m provides fundamental understanding of its dynamics in linear and nonlinear regimes. Furthermore, we discuss magnetization reversal as a function of DMI and anisotropy energy induced by a spin current pulse.

SUBMITTER: Kim TH

PROVIDER: S-EPMC5054374 | biostudies-other | 2016 Oct

REPOSITORIES: biostudies-other

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Ultrafast spin dynamics and switching via spin transfer torque in antiferromagnets with weak ferromagnetism.

Kim Tae Heon TH Grünberg Peter P Han Song Hee SH Cho Beongki B

Scientific reports 20161007

The spin-torque driven dynamics of antiferromagnets with Dzyaloshinskii-Moriya interaction (DMI) were investigated based on the Landau-Lifshitz-Gilbert-Slonczewski equation with antiferromagnetic and ferromagnetic order parameters (l and m, respectively). We demonstrate that antiferromagnets including DMI can be described by a 2-dimensional pendulum model of l. Because m is coupled with l, together with DMI and exchange energy, close examination of m provides fundamental understanding of its dyn ...[more]

PMID: 27713522

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