Dynamic correlation functions in one-dimensional quasi-condensates

D. L. Luxat; A. Griffin

doi:10.1103/physreva.67.043603

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arXiv · cond-mat/0212103

Dynamic correlation functions in one-dimensional quasi-condensates

D. L. Luxat·A. Griffin

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Abstract

We calculate the static and dynamic single-particle correlation functions in one-dimensional (1D) trapped Bose gases and discuss experimental measurements that can directly probe such correlation functions. Using a quantized hydrodynamic theory for the low energy excitations, we calculate both the static and dynamic single-particle correlation functions for a 1D Bose gas that is a phase-fluctuating quasi-condensate. For the static (equal-time) correlation function, our approximations and results are equivalent to those of Petrov, Shlyapnikov and Walraven. The Fourier transform of the static single-particle correlation function gives the momentum distribution, which can be measured using Doppler-sensitive Bragg scattering experiments on a highly elongated Bose gas. We show how a two-photon Raman out-coupling experiment can measure the characteristic features of the dynamic or time-dependent single-particle correlation function of a 1D Bose quasi-condensate.

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D. L. Luxat, A. Griffin. 2002-12-04. Dynamic correlation functions in one-dimensional quasi-condensates. https://doi.org/10.1103/physreva.67.043603

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