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Quantum Monte Carlo simulation of a two-dimensional Bose gas

S. Pilati·J. Boronat·J. Casulleras·S. Giorgini
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Abstract

The equation of state of a homogeneous two-dimensional Bose gas is calculated using quantum Monte Carlo methods. The low-density universal behavior is investigated using different interatomic model potentials, both finite-ranged and strictly repulsive and zero-ranged supporting a bound state. The condensate fraction and the pair distribution function are calculated as a function of the gas parameter, ranging from the dilute to the strongly correlated regime. In the case of the zero-range pseudopotential we discuss the stability of the gas-like state for large values of the two-dimensional scattering length, and we calculate the critical density where the system becomes unstable against cluster formation.

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S. Pilati, J. Boronat, J. Casulleras, S. Giorgini. 2004-11-02. Quantum Monte Carlo simulation of a two-dimensional Bose gas. https://doi.org/10.1103/physreva.71.023605

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