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Images of a Bose-Einstein condensate: diagonal dynamical Bogoliubov vacuum

Jacek Dziarmaga·Krzysztof Sacha
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Abstract

Evolution of a Bose-Einstein condensate subject to a time-dependent external perturbation can be described by a time-dependent Bogoliubov theory: a condensate initially in its ground state Bogoliubov vacuum evolves into a time-dependent excited state which can be formally written as a time-dependent Bogoliubov vacuum annihilated by time-dependent quasiparticle annihilation operators. We prove that any Bogoliubov vacuum can be brought to a diagonal form in a time-dependent orthonormal basis. This diagonal form is tailored for simulations of quantum measurements on an excited condensate. As an example we work out phase imprinting of a dark soliton followed by a density measurement.

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Jacek Dziarmaga, Krzysztof Sacha. 2005-03-14. Images of a Bose-Einstein condensate: diagonal dynamical Bogoliubov vacuum. https://doi.org/10.1088/0953-4075%2F39%2F1%2F007

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