Charge-stripe phases versus a weak anisotropy of nearest-neighbor hopping

V. Derzhko; J. Jedrzejewski

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Charge-stripe phases versus a weak anisotropy of nearest-neighbor hopping

V. Derzhko·J. Jedrzejewski

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Abstract

Recently, we demonstrated rigorously the stability of charge-stripe phases in quantum-particle systems that are described by extended Falicov-Kimball Hamiltonians, with the quantum hopping particles being either spinless fermions or hardcore bosons. In this paper, by means of the same methods, we show that any anisotropy of nearest-neighbor hopping eliminates the $π/2$-rotation degeneracy of the so called dimeric and axial-stripe phases and orients them in the direction of a weaker hopping. Moreover, due to the same anisotropy the obtained phase diagrams of fermions show a tendency to become similar to those of hardcore bosons.

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V. Derzhko, J. Jedrzejewski. 2005-11-23. Charge-stripe phases versus a weak anisotropy of nearest-neighbor hopping. https://arxiv.org/abs/cond-mat/0509698

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