Single-particle and collective excitations in a charged Bose gas at finite temperature

B. Davoudi; M. P. Tosi

doi:10.1103/physrevb.72.134520

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Single-particle and collective excitations in a charged Bose gas at finite temperature

B. Davoudi·M. P. Tosi

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Abstract

The main focus of this work is on the predictions made by the dielectric formalism in regard to the relationship between single-particle and collective excitation spectra in a gas of point-like charged bosons at finite temperature $T$ below the critical region of Bose-Einstein condensation. Illustrative numerical results at weak coupling ($r_s = 1$) are presented within the Random Phase Approximation. We show that within this approach the single-particle spectrum forms a continuum extending from the transverse to the longitudinal plasma mode frequency and leading to a double-peak structure as $T$ increases, whereas the density fluctuation spectrum consists of a single broadening peak. We also discuss the momentum distribution and the superfluidity of the gas.

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BibTeX RIS

B. Davoudi, M. P. Tosi. 2005-06-07. Single-particle and collective excitations in a charged Bose gas at finite temperature. https://doi.org/10.1103/physrevb.72.134520

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