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arXiv · 2605.09705

Spin-charge separation in two-leg t-J ladders

Luhang Yang·Elbio Dagotto
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Abstract

Spin-charge separation is a hallmark of one-dimensional fermionic systems, yet its realization in higher dimensions remains an open question. To address this issue, we investigate a two-leg t-J ladder using the density matrix renormalization group (DMRG) method and its time-dependent extension. By analyzing ground-state correlations and single-particle removal spectra, we systematically examine the effects of plaquette diagonal hopping, spin exchange, and hole doping. Within appropriate parameter regimes, these factors drive the system from the well-known Luther Emery phase, with gapped spin and gapless charge modes, into a Luttinger liquid phase characterized by gapless spin and charge excitations, where signatures of spin-charge separation emerge. In combination with previous studies using exact diagonalization, our results provide evidence that spin-charge separation may persist in wider ladder systems.

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Luhang Yang, Elbio Dagotto. 2026-05-10. Spin-charge separation in two-leg t-J ladders. https://arxiv.org/abs/2605.09705

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