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arXiv · 1101.1669

Bose-Einstein condensation and a two-dimensional walk model

Farhad H. Jafarpour
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Abstract

We introduce a two-dimensional walk model in which a random walker can only move on the first quarter of a two-dimensional plane. We calculate the partition function of this walk model using a transfer matrix method and show that the model undergoes a phase-transition. Surprisingly the partition function of this two-dimensional walk model is exactly equal to that of a driven-diffusive system defined on a discrete lattice with periodic boundary conditions in which a phase transition occurs from a high-density to a low-density phase. The driven-diffusive system can be mapped to a zero-range process where the particles can accumulate in a single lattice site in the low-density phase. This is very reminiscent of real-space Bose-Einstein condensation.

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BibTeXRIS

Farhad H. Jafarpour. 2011-01-09. Bose-Einstein condensation and a two-dimensional walk model. https://doi.org/10.1103/physreve.83.041112

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