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arXiv:2605.03582 · Physical review. B./Physical review. B

Renormalization group analysis for bosonization coefficients in half-odd-integer Kitaev spin chains

Jianxun Li, Chao Xu, Wang Yang

Published Sep 21, 2026• 0 citations
arXivHTMLPDF

Abstract

Based on a renormalization-group (RG) analysis, we study the bosonization formulas for spin-$S$ Kitaev-Gamma and Kitaev-Heisenberg-Gamma chains in the parameter regime $K<0$, $Γ>0$, and $J>0$, with $S$ being a half-odd integer. We find that the effects associated with the breaking of emergent continuous symmetries in the bosonization formulas scale as $1/S$ in the large-$S$ limit, in qualitative agreement with density-matrix renormalization-group (DMRG) results for Kitaev-Gamma chains. For Kitaev-Heisenberg-Gamma chains, the low-energy excitations are characterized by incommensurate gapless wave vectors, and symmetry analysis yields ten independent bosonization coefficients, five of which are predicted by the RG analysis to be independent of the Heisenberg coupling up to linear order. Our results provide useful input for determining magnetic ordering tendencies in two-dimensional Kitaev spin models within a quasi-one-dimensional approach.

DOI
10.1103/bnfb-z5qh

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