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arXiv · 2209.10390

From Kosterlitz-Thouless to Pokrovsky-Talapov transitions in spinless fermions and spin chains with next-nearest neighbour interactions

Natalia Chepiga
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Abstract

We investigate the nature of the quantum phase transition out of charge-density-wave phase in the spinless fermion model with nearest- and next-nearest-neighbor interaction at one-third filling. Using an extensive Density Matrix Renormalization Group (DMRG) simulations we show that the transition changes it nature. We show that for weak next-nearest-neighbor coupling the transition is of Kosterlitz-Thouless type in agreement with bosonisation predictions. We also provide strong numerical evidences that for large next-nearest-neighbor repulsion the transition belongs to the Pokrovsky-Talapov univerality class describing a non-conformal commensurate-incommensurate transition. Finally, we argue that the change of the nature of the transition is a result of incommensurability induced by frustration and realized even at zero doping. The implications in the context of XXZ chain with next-nearest-neighbor Ising interaction is briefly discussed.

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Natalia Chepiga. 2022-09-21. From Kosterlitz-Thouless to Pokrovsky-Talapov transitions in spinless fermions and spin chains with next-nearest neighbour interactions. https://doi.org/10.1103/physrevresearch.4.043225

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