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arXiv · 2206.01325

Skyrmion formation in Ni-based Janus dihalide monolayers: Interplay between magnetic frustration and Dzyaloshinskii-Moriya interaction

Taylan Gorkan·Jyotirish Das·Jesse Kapeghian·Muhammad Akram·Johannes V. Barth·Sefaattin Tongay·Ethem Akturk·Onur Erten·Antia Botana
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Abstract

We present a comprehensive theory of the magnetic phases in monolayer nickel-based Janus dihalides (NiIBr, NiICl, NiBrCl) through a combination of first-principles calculations and atomistic simulations. Phonon band structure calculations and finite temperature molecular dynamics simulations show that Ni-dihalide Janus monolayers are stable. The parameters of the interacting spin Hamiltonian extracted from ab initio calculations show that nickel-dihalide Janus monolayers exhibit varying degrees of magnetic frustration together with a large Dzyaloshinskii-Moriya interaction due to their inherent inversion symmetry breaking. The atomistic simulations reveal a delicate interplay between these two competing magnetic interactions in giving rise to skyrmion formation.

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Taylan Gorkan, Jyotirish Das, Jesse Kapeghian, Muhammad Akram, Johannes V. Barth, Sefaattin Tongay, Ethem Akturk, Onur Erten, Antia Botana. 2022-06-02. Skyrmion formation in Ni-based Janus dihalide monolayers: Interplay between magnetic frustration and Dzyaloshinskii-Moriya interaction. https://arxiv.org/abs/2206.01325

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