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arXiv · 2005.03195

Pressure-dependent Intermediate Magnetic Phase in Thin Fe$_3$GeTe$_2$ Flakes

Heshen Wang·Runzhang Xu·Cai Liu·Le Wang·Zhan Zhang·Huimin Su·Shanmin Wang·Yusheng Zhao·Zhaojun Liu·Dapeng Yu·Jia-Wei Mei·Xiaolong Zou·Jun-Feng Dai
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Abstract

We investigated the evolution of ferromagnetism in layered Fe$_3$GeTe$_2$ flakes under different pressures and temperatures using in situ magnetic circular dichroism (MCD) spectroscopy. We found that the rectangle shape of hysteretic loop under an out-of-plane magnetic field sweep can sustain below 7 GPa. Above that pressure, an intermediate state appears at low temperature region signaled by an 8-shaped skew hysteretic loop. Meanwhile, the coercive field and Curie temperature decrease with increasing pressures, implying the decrease of the exchange interaction and the magneto-crystalline anisotropy under pressures. The intermediate phase has a labyrinthine domain structure, which is attributed to the increase of ratio of exchange interaction to magneto-crystalline anisotropy based on Jagla's theory. Moreover, our calculation results reveal a weak structural transition around 6 GPa, which leads to a drop of the magnetic momentum of Fe ions.

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Heshen Wang, Runzhang Xu, Cai Liu, Le Wang, Zhan Zhang, Huimin Su, Shanmin Wang, Yusheng Zhao, Zhaojun Liu, Dapeng Yu, Jia-Wei Mei, Xiaolong Zou, Jun-Feng Dai. 2020-05-07. Pressure-dependent Intermediate Magnetic Phase in Thin Fe$_3$GeTe$_2$ Flakes. https://arxiv.org/abs/2005.03195

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