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Slave-boson approach to the infinite-U Anderson-Holstein impurity model

Hyun C. Lee·Han-Yong Choi
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Abstract

The infinite-$U$ Anderson-Holstein impurity model is studied with a focus on the interplay between the strong electron correlation and the weak electron-phonon interaction. The slave boson method has been employed in combination with the large degeneracy expansion (1/N) technique. The charge and spin susceptibilities and the phonon propagator are obtained in the approximation scheme where the saddle point configuration and the Gaussian 1/N fluctuations are taken into account. The spin susceptibility is found not to be renormalized by electron-phonon interaction, while the charge susceptibility is renormalized. From the renormalized charge susceptibility the Kondo temperature is found to increase by the electron-phonon interaction. It turns out that the bosonic 1/N Gaussian fluctuations play a very crucial role, in particular, for the phonon propagator.

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Hyun C. Lee, Han-Yong Choi. 2004-08-31. Slave-boson approach to the infinite-U Anderson-Holstein impurity model. https://doi.org/10.1103/physrevb.70.085114

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