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Experimental observation of the Bogoliubov transformation for a Bose-Einstein condensed gas

J. M. Vogels·K. Xu·C. Raman·J. R. Abo-Shaeer·W. Ketterle
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Abstract

Phonons with wavevector $q/\hbar$ were optically imprinted into a Bose-Einstein condensate. Their momentum distribution was analyzed using Bragg spectroscopy with a high momentum transfer. The wavefunction of the phonons was shown to be a superposition of +q and -q free particle momentum states, in agreement with the Bogoliubov quasiparticle picture.

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J. M. Vogels, K. Xu, C. Raman, J. R. Abo-Shaeer, W. Ketterle. 2001-12-06. Experimental observation of the Bogoliubov transformation for a Bose-Einstein condensed gas. https://doi.org/10.1103/physrevlett.88.060402

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