Efficient iPEPS simulation on the honeycomb lattice via QR-based corner transfer matrix renormalization group
Phys. Rev. B 113, 085109 – Published 5 February, 2026
DOI: https://doi.org/10.1103/9gmp-byx8
Abstract
We develop a QR-based corner transfer matrix renormalization group (CTMRG) framework for contracting infinite projected entangled-pair states on honeycomb lattices. Our method explicitly uses the lattice's native symmetry at each site, generalizing QR-based acceleration (previously limited to square lattices) to enable efficient and stable contractions. This approach achieves order-of-magnitude speedups over conventional singular value decomposition-based CTMRG while maintaining high numerical precision. Comprehensive benchmark calculations for the spin-1/2 Heisenberg and Kitaev models demonstrate higher computational efficiency without sacrificing accuracy. We further employ our method to study the Kitaev-Heisenberg model, where we provide numerical evidence for the universal decay of the dimer-dimer correlation function within the quantum spin liquid phase. Our work establishes a framework for extending QR-based CTMRG to other lattice geometries, opening alternative avenues for studying exotic quantum phases with tensor networks.