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arXiv · 1902.07961

Exchange Intervalley Scattering And Magnetic Phase Diagram Of Transition Metal Dichalcogenide Monolayers

Dmitry Miserev·Jelena Klinovaja·Daniel Loss
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Abstract

We analyze magnetic phases of monolayers of transition metal dichalcogenides that are two-valley materials with electron-electron interactions. The exchange inter-valley scattering makes two-valley systems less stable to the spin fluctuations but more stable to the valley fluctuations. We predict a first order ferromagnetic phase transition governed by the non-analytic and negative cubic term in the free energy that results in a large spontaneous spin magnetization. Finite spin-orbit interaction leads to the out-of-plane Ising order of the ferromagnetic phase. Our theoretical prediction is consistent with the recent experiment on electron-doped monolayers of MoS$_2$ reported by Roch $\textit{et al.}$ [1]. The proposed first order phase transition can also be tested by measuring the linear magnetic field dependence of the spin susceptibility in the paramagnetic phase which is a direct consequence of the non-analyticity of the free energy.

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Dmitry Miserev, Jelena Klinovaja, Daniel Loss. 2019-07-11. Exchange Intervalley Scattering And Magnetic Phase Diagram Of Transition Metal Dichalcogenide Monolayers. https://doi.org/10.1103/physrevb.100.014428

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