Collective Excitations of Dilute Bose-Fermi Superfluid Mixtures

Bernhard Hikaru Valtan; Munehiro Nishida; Susumu Kurihara

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Collective Excitations of Dilute Bose-Fermi Superfluid Mixtures

Bernhard Hikaru Valtan·Munehiro Nishida·Susumu Kurihara

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Abstract

Using the effective action formalism, we investigate collective excitations of a dilute mixture of a Bose gas and a two component Fermi gas when both bosons and fermions have undergone superfluid transitions. We show that there is a repulsion between Bogoliubov and Anderson modes, which has important implications including disappearance of boson superfluidity. We derive an analytic expression for the long-wavelength dispersion relation of the mixture at zero temperature and give a condition for the instability. We also numerically calculate the damping rate due to boson-fermion interaction at finite temperatures and show that the two modes are stable at sufficiently low temperatures.

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Bernhard Hikaru Valtan, Munehiro Nishida, Susumu Kurihara. 2001-06-25. Collective Excitations of Dilute Bose-Fermi Superfluid Mixtures. https://arxiv.org/abs/cond-mat/0106503

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