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arXiv · 1310.0601

Spin wave theory for 2D disordered hard-core bosons

Juan Pablo Álvarez Zúñiga·Gabriel Lemarié·Nicolas Laflorencie
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Abstract

A spin-wave (SW) approach for hard-core bosons is presented to treat the problem of two dimensional boson localization in a random potential. After a short review of the method to compute 1/S-corrected observables, the case of random on-site energy is discussed. Whereas the mean-field solution does not display a Bose glass (BG) phase, 1/S corrections do capture BG physics. In particular, the localization of SW excitations is discussed through the inverse participation ratio.

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Juan Pablo Álvarez Zúñiga, Gabriel Lemarié, Nicolas Laflorencie. 2013-10-02. Spin wave theory for 2D disordered hard-core bosons. https://doi.org/10.1063/1.4893518

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