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arXiv · 1601.06213

Nonlinear magnetization dynamics of antiferromagnetic spin resonance induced by intense terahertz magnetic field

Y Mukai·H Hirori·T Yamamoto·H Kageyama·K Tanaka
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Abstract

We report on the nonlinear magnetization dynamics of a HoFeO3 crystal induced by a strong terahertz magnetic field resonantly enhanced with a split ring resonator and measured with magneto-optical Kerr effect microscopy. The terahertz magnetic field induces a large change (~40%) in the spontaneous magnetization. The frequency of the antiferromagnetic resonance decreases in proportion to the square of the magnetization change. A modified Landau-Lifshitz-Gilbert equation with a phenomenological nonlinear damping term quantitatively reproduced the nonlinear dynamics.

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Y Mukai, H Hirori, T Yamamoto, H Kageyama, K Tanaka. 2016-01-23. Nonlinear magnetization dynamics of antiferromagnetic spin resonance induced by intense terahertz magnetic field. https://doi.org/10.1088/1367-2630%2F18%2F1%2F013045

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