Effective action approach to the Leggett's mode in two-band superconductors

S. G. Sharapov; V. P. Gusynin; H. Beck

doi:10.1140/epjb/e2002-00356-9

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Effective action approach to the Leggett's mode in two-band superconductors

S. G. Sharapov·V. P. Gusynin·H. Beck

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Abstract

We investigate a collective excitation (Leggett's mode) corresponding to small fluctuations of the relative phase of two condensates in two-band superconductor using the effective ``phase only'' action. We consider the possibility of observing Leggett's mode in MgB$_2$ superconductor and conclude that for the known at present values of the two-band model parameters for MgB$_2$ Leggett's mode arises above the two-particle threshold.

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S. G. Sharapov, V. P. Gusynin, H. Beck. 2002-11-19. Effective action approach to the Leggett's mode in two-band superconductors. https://doi.org/10.1140/epjb%2Fe2002-00356-9

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