Rotons in a hybrid Bose-Fermi system.
نویسندگان
چکیده
We calculate the spectrum of elementary excitations in a two-dimensional exciton condensate in the vicinity of a two-dimensional electron gas. We show that attraction of excitons due to their scattering with free electrons may lead to formation of a roton minimum. The energy of this minimum may go below the ground state energy which manifests breaking of the superfluidity. The Berezinsky-Kosterlitz-Thouless phase transition temperature decreases due to the exciton-exciton attraction mediated by electrons.
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ورودعنوان ژورنال:
- Physical review letters
دوره 105 14 شماره
صفحات -
تاریخ انتشار 2010