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arXiv · 2607.09421

Short-range magnetic order and multi-stage phase transitions in the easy-plane van der Waals magnet CrCl$_3$

Abstract

We investigate the evolution of spin correlations and the nature of the multi-stage magnetic transition in the quasi-two-dimensional easy-plane van der Waals magnet $\rm CrCl_3$. By combining broadband ferromagnetic resonance (FMR) spectroscopy and DC SQUID magnetometry on mechanically exfoliated micro-flakes with non-local dynamical mean-field theory (DFT+DMFT) calculations, we analyze both long- and short range magnetic order in CrCl$_3$. Experimentally, SQUID and FMR measurements confirm the presence of the crossover to a spin polarized phase with the subsequent transition into an antiferromagnetic ground state upon cooling, but show robust short-range correlations at temperatures far above the magnetic ordering temperatures. Theoretically, we show the existence of highly stable local magnetic moments at room temperature, with a giant room temperature lifetime $τ$ of 130--300 ps due to a wide Mott bandgap. Below room temperature, a rapid growth of the in-plane correlation length $ξ$ signals the formation of strong short range magnetic order consistent with the experimental observations. We also obtain a temperature-driven crossover of the interlayer exchange interaction, which changes from positive (ferromagnetic) at high temperatures to negative (antiferromagnetic) in the low-temperature ordered phase.

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T. B. Mazitov, M. I. Panin, A. S. Pakhomov, M. V. Bakhmetiev, E. O. Chiglintsev, A. I. Chernov, A. A. Katanin. 2026-07-10. Short-range magnetic order and multi-stage phase transitions in the easy-plane van der Waals magnet CrCl$_3$. https://arxiv.org/abs/2607.09421

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