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Damping of long-wavelength collective excitations in quasi-onedimensional Fermi liquids

F. Capurro·M. Polini·M. P. Tosi
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Abstract

The imaginary part of the exchange-correlation kernel in the longitudinal current-current response function of a quasi-onedimensional Fermi liquid is evaluated by an approximate decoupling in the equation of motion for the current density, which accounts for processes of excitation of two particle-hole pairs. The two-pair spectrum determines the intrinsic damping rate of long-wavelength collective density fluctuations, which is calculated and contrasted with a result previously obtained for a clean Luttinger liquid.

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F. Capurro, M. Polini, M. P. Tosi. 2002-09-19. Damping of long-wavelength collective excitations in quasi-onedimensional Fermi liquids. https://doi.org/10.1016/s0921-4526(02)01541-7

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