Disordered bosons: Condensate and excitations.
نویسندگان
چکیده
The disordered Bose Hubbard model is studied numerically within the Bogoliubov approximation. First, the spatially varying condensate wavefunction in the presence of disorder is found by solving a nonlinear Schrodinger equation. Using the Bogoliubov approximation to find the excitations above this condensate, we calculate the condensate fraction, superfluid density, and density of states for a two-dimensional disordered system. These results are compared with experiments done with 4He adsorbed in porous media. Typeset using REVTEX 1
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ورودعنوان ژورنال:
- Physical review. B, Condensed matter
دوره 49 13 شماره
صفحات -
تاریخ انتشار 1994