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arXiv · 2004.12954

Comprehensive study of the phase diagram of the spin-1/2 Kitaev-Heisenberg-Gamma chain

Wang Yang·Alberto Nocera·Ian Affleck
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Abstract

A central question on Kitaev materials is the effects of additional couplings on the Kitaev model which is proposed to be a candidate for realizing topological quantum computations. However, two spatial dimension typically suffers the difficulty of lacking controllable approaches. In this work, using a combination of powerful analytical and numerical methods available in one dimension, we perform a comprehensive study on the phase diagram of a one-dimensional version of the spin-1/2 Kitaev-Heisenberg-Gamma model in its full parameter space. A strikingly rich phase diagram is found with nine distinct phases, including four Luttinger liquid phases, a ferromagnetic phase, a N\'eel ordered phase, an ordered phase of distorted-spiral spin alignments, and two ordered phase which both break a $D_3$ symmetry albeit in different ways, where $D_3$ is the dihedral group of order six. Our work paves the way for studying one-dimensional Kitaev materials and may provide hints to the physics in higher dimensional situations.

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Wang Yang, Alberto Nocera, Ian Affleck. 2020-04-27. Comprehensive study of the phase diagram of the spin-1/2 Kitaev-Heisenberg-Gamma chain. https://doi.org/10.1103/physrevresearch.2.033268

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