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arXiv · 2111.05465

Observation of spontaneous x-ray magnetic circular dichroism in a chiral antiferromagnet

Shoya Sakamoto·Tomoya Higo·Masanobu Shiga·Kenta Amemiya·Satoru Nakatsuji·Shinji Miwa
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Abstract

X-ray magnetic circular dichroism (XMCD) signals are usually absent in antiferromagnets. In this letter, we report the observation of spontaneous XMCD spectra originating from the inverse triangular spin structure, or the polarization of the cluster magnetic octupole, in the chiral antiferromagnet Mn$_{3}$Sn thin film. The result is consistent with the recent theoretical predictions that the inverse triangular spin structure can give rise to finite XMCD signals in the absence of net magnetization [J. Phys. Soc. Jpn. 89, 083703 (2020) and Phys. Rev. Lett. 126, 157402 (2021)].

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Shoya Sakamoto, Tomoya Higo, Masanobu Shiga, Kenta Amemiya, Satoru Nakatsuji, Shinji Miwa. 2021-11-10. Observation of spontaneous x-ray magnetic circular dichroism in a chiral antiferromagnet. https://doi.org/10.1103/physrevb.104.134431

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