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arXiv · 2304.08422

Phase diagram of the Kitaev-Heisenberg model using various finite-size clusters

Masahiro Kadosawa·Masaaki Nakamura·Yukinori Ohta·Satoshi Nishimoto
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Abstract

We estimate phase boundaries of four ordered and two spin-liquid phases for the spin-$\frac{1}{2}$ Kitaev-Heisenberg (KH) model using four kinds of relatively-small clusters, based on the second derivative of ground-state energy. The estimated values are compared between the clusters as well as the previous iPEPS results. We thus find that the boundaries can be accurately estimated within limited-size clusters. The used clusters may appropriate to study higher-$S$ KH models having less fluctuations.

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Masahiro Kadosawa, Masaaki Nakamura, Yukinori Ohta, Satoshi Nishimoto. 2023-04-17. Phase diagram of the Kitaev-Heisenberg model using various finite-size clusters. https://doi.org/10.7566/jpsj.92.055001

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