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Kosterlitz-Thouless transition of quantum XY model in two dimensions

Kenji Harada·Naoki Kawashima
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Abstract

The two-dimensional $S=1/2$ XY model is investigated with an extensive quantum Monte Carlo simulation. The helicity modulus is precisely estimated through a continuous-time loop algorithm for systems up to $128 \times 128$ near and below the critical temperature. The critical temperature is estimated as $T_{\rm KT} = 0.3427(2)J$. The obtained estimates for the helicity modulus are well fitted by a scaling form derived from the Kosterlitz renormalization group equation. The validity of the Kosterlitz-Thouless theory for this model is confirmed.

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Kenji Harada, Naoki Kawashima. 1998-09-22. Kosterlitz-Thouless transition of quantum XY model in two dimensions. https://doi.org/10.1143/jpsj.67.2768

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