An exact stochastic field method for the interacting Bose gas at thermal equilibrium

@article{Carusotto2001AnES,
  title={An exact stochastic field method for the interacting Bose gas at thermal equilibrium},
  author={Iacopo Carusotto and Yvan Castin},
  journal={Journal of Physics B},
  year={2001},
  volume={34},
  pages={4589-4608}
}
We present a new exact method to numerically compute the thermodynamical properties of an interacting Bose gas in the canonical ensemble. As in our previous paper (Carusotto I, Castin Y and Dalibard J 2001 Phys. Rev. A 63 023606), we write the density operator ρ as an average of Hartree dyadics |N:1N:2| and we find stochastic evolution equations for the wavefunctions 1,2 such that the exact imaginary-time evolution of ρ is recovered after averaging over noise. In this way, the thermal… 

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