Experimental observation of the Bogoliubov transformation for a Bose-Eeinstein condensed gas.
نویسندگان
چکیده
Phonons with wave vector q/(planck constant) were optically imprinted into a Bose-Einstein condensate. Their momentum distribution was analyzed using Bragg spectroscopy with a high momentum transfer. The wave function of the phonons was shown to be a superposition of +q and -q free particle momentum states, in agreement with the Bogoliubov quasiparticle picture.
منابع مشابه
Experimental observation of the Bogoliubov transformation for a Bose-Einstein condensed gas
The pioneering paper by Bogoliubov in 1947 was the starting point for a microscopic theory of superfluidity [1]. Bogoliubov found the non-perturbative solution for a weakly interacting gas of bosons. The main step in the diagonalization of the Hamiltonian is the famous Bogoliubov transformation, which expresses the elementary excitations (or quasiparticles) with momentum q in terms of the free ...
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عنوان ژورنال:
- Physical review letters
دوره 88 6 شماره
صفحات -
تاریخ انتشار 2002