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arXiv · 2212.05434

Fluctuation-induced first order phase transitions in Kitaev-like $d^4$ honeycomb magnet

Yuchen Fan·Yuan Wan
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Abstract

We study numerically a bosonic analog of the Kitaev honeycomb model, which is a minimal model for $4d^4/5d^4$ quantum magnets with honeycomb lattice geometry. We construct its phase diagram by a combination of Landau theory analysis and quantum Monte Carlo simulations. In particular, we show that the phase boundaries between the paramagnetic state and magnetically ordered states are generically fluctuation-induced first order phase transitions. Our results are potentially applicable to Ru$^{4+}$- and Ir$^{5+}$-based honeycomb magnets.

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Yuchen Fan, Yuan Wan. 2022-12-11. Fluctuation-induced first order phase transitions in Kitaev-like $d^4$ honeycomb magnet. https://doi.org/10.1103/physrevb.107.075130

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