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Visco-elastic spectra of a dilute Bose fluid

A. Minguzzi·M. P. Tosi
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Abstract

A recently developed local-density current functional formalism for confined Bose-condensed superfluids requires visco-elastic spectra which are defined through a finite-frequency extension of the dissipative coefficients entering the linearized hydrodynamic equations of the two-fluid model. We evaluate these spectra for a superfluid with contact interactions in the collisionless regime at finite temperature, by working to first order beyond the Bogolubov approximation. We find that within this approximation all the visco-elastic spectra take the same value aside from simple multiplicative factors.

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A. Minguzzi, M. P. Tosi. 1998-09-22. Visco-elastic spectra of a dilute Bose fluid. https://doi.org/10.1016/s0921-4526(98)01090-4

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