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arXiv · 2005.14189

Nonequilibrium quasistationary spin disordered state in the Kitaev-Heisenberg magnet $\alpha$-RuCl$_3$

R. B. Versteeg·A. Chiocchetta·F. Sekiguchi·A. I. R. Aldea·A. Sahasrabudhe·K. Budzinauskas·Zhe Wang·V. Tsurkan·A. Loidl·D. I. Khomskii·S. Diehl·P. H. M. van Loosdrecht
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Abstract

Excitation by light pulses enables the manipulation of phases of quantum condensed matter. Here, we photoexcite high-energy holon-doublon pairs as a way to alter the magnetic free energy landscape of the Kitaev-Heisenberg magnet $\alpha$-RuCl$_3$, with the aim to dynamically stabilize a proximate spin liquid phase. The holon-doublon pair recombination through multimagnon emission is tracked through the time-evolution of the magnetic linear dichroism originating from the competing zigzag spin ordered ground state. A small holon-doublon density suffices to reach a spin disordered state. The phase transition is described within a dynamic Ginzburg-Landau framework, corroborating the quasistationary nature of the transient spin disordered phase. Our work provides insight into the coupling between the electronic and magnetic degrees of freedom in $\alpha$-RuCl$_3$ and suggests a new route to reach a proximate spin liquid phase in Kitaev-Heisenberg magnets.

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R. B. Versteeg, A. Chiocchetta, F. Sekiguchi, A. I. R. Aldea, A. Sahasrabudhe, K. Budzinauskas, Zhe Wang, V. Tsurkan, A. Loidl, D. I. Khomskii, S. Diehl, P. H. M. van Loosdrecht. 2020-05-28. Nonequilibrium quasistationary spin disordered state in the Kitaev-Heisenberg magnet $\alpha$-RuCl$_3$. https://arxiv.org/abs/2005.14189

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