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arXiv · 0707.3930

Superfluid-Insulator and Roughening Transitions in Domain Walls

Ş. G. Söyler·B. Capogrosso-Sansone·N. V. Prokof'ev·B. V. Svistunov
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Abstract

We have performed quantum Monte Carlo simulations to investigate the superfluid behavior of one- and two-dimensional interfaces separating checkerboard solid domains. The system is described by the hard-core Bose-Hubbard Hamiltonian with nearest-neighbor interaction. In accordance with Ref.1, we find that (i) the interface remains superfluid in a wide range of interaction strength before it undergoes a superfluid-insulator transition; (ii) in one dimension, the transition is of the Kosterlitz-Thouless type and is accompanied by the roughening transition, driven by proliferation of charge 1/2 quasiparticles; (iii) in two dimensions, the transition belongs to the 3D U(1) universality class and the interface remains smooth. Similar phenomena are expected for domain walls in quantum antiferromagnets.

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Ş. G. Söyler, B. Capogrosso-Sansone, N. V. Prokof'ev, B. V. Svistunov. 2007-11-27. Superfluid-Insulator and Roughening Transitions in Domain Walls. https://doi.org/10.1103/physreva.76.043628

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