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arXiv · 2107.03045

Quantum liquid crystals in the finite-field K$\Gamma$ model for $\alpha$-RuCl$_3$

Masahiko G. Yamada·Satoshi Fujimoto
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Abstract

We study the extended Kitaev model called the K$\Gamma$ model, using a perturbative expansion combined with a well-controlled mean-field approximation and a cutting-edge exact diagonalization. In the phase diagram, we discover a nematic Kitaev spin liquid and a Kekul\'e Kitaev spin liquid. The former potentially explains the high-field nematic state with zero Chern number experimentally observed in $\alpha$-RuCl$_3$, even for sufficiently small values of $\Gamma/|K|$. The latter has a Majorana zero mode in its $Z_3$ vortex core, which can be potentially controlled by the domain wall motion. This opens a possible application of the quantum liquid crystal phases in the K$\Gamma$ model to the topological quantum computation.

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Masahiko G. Yamada, Satoshi Fujimoto. 2021-07-07. Quantum liquid crystals in the finite-field K$\Gamma$ model for $\alpha$-RuCl$_3$. https://arxiv.org/abs/2107.03045

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