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arXiv · 1806.02889

Equation of state of the one- and three-dimensional Bose-Bose gases

Emerson Chiquillo
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Abstract

We calculate the equation of state of Bose-Bose gases in one and three dimensions in the framework of an effective quantum field theory. The beyond-mean-field approximation at zero-temperature and the one-loop finite-temperature results are obtained performing functional integration on a local effective action. The ultraviolet divergent zero-point quantum fluctuations are removed by means of dimensional regularization. We derive the nonlinear Schrödinger equation to describe one- and three-dimensional Bose-Bose mixtures and solve it analytically in the one-dimensional scenario. This equation supports self-trapped brightlike solitonic-droplets and self-trapped darklike solitons. At low temperature, we also find that the pressure and the number of particles of symmetric quantum droplets have a nontrivial dependence on the chemical potential and the difference between the intra- and the inter-species coupling constants.

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Emerson Chiquillo. 2018-06-07. Equation of state of the one- and three-dimensional Bose-Bose gases. https://doi.org/10.1103/physreva.97.063605

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