Magnon gap excitations in van der Waals antiferromagnet MnPSe$_3$

Dipankar Jana; D. Vaclavkova; I. Mohelsky; P. Kapuscinski; C. W. Cho; I. Breslavetz; M. Białek; J. -Ph. Ansermet; B. A. Piot; M. Orlita; C. Faugeras; M. Potemski

arXiv · 2309.06866

Magnon gap excitations in van der Waals antiferromagnet MnPSe$_3$

Dipankar Jana·D. Vaclavkova·I. Mohelsky·P. Kapuscinski·C. W. Cho·I. Breslavetz·M. Białek·J. -Ph. Ansermet·B. A. Piot·M. Orlita·C. Faugeras·M. Potemski

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Abstract

Magneto-spectroscopy methods have been employed to study the zero-wavevector magnon excitations in MnPSe$_3$. Experiments carried out as a function of temperature and the applied magnetic field show that two low-energy magnon branches of MnPSe$_3$ in its antiferromagnetic phase are gapped. The observation of two low-energy magnon gaps (at 14 and 0.7 cm$^{-1}$) implies that MnPSe$_3$ is a biaxial antiferromagnet. A relatively strong out-of-plane anisotropy imposes the spin alignment to be in-plane whereas the spin directionality within the plane is governed by a factor of 2.5 $\times$ 10$^{-3}$ weaker in-plane anisotropy.

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Dipankar Jana, D. Vaclavkova, I. Mohelsky, P. Kapuscinski, C. W. Cho, I. Breslavetz, M. Białek, J. -Ph. Ansermet, B. A. Piot, M. Orlita, C. Faugeras, M. Potemski. 2023-09-13. Magnon gap excitations in van der Waals antiferromagnet MnPSe$_3$. https://arxiv.org/abs/2309.06866

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