Gap formation and soft phonon mode in the Holstein model.
We investigate electron-phonon coupling in many-electron systems using the dynamical mean-field theory in combination with the numerical renormalization group. This nonperturbative method reveals significant precursor effects to the gap formation at intermediate coupling strengths. The emergence of a soft phonon mode and very strong lattice fluctuations can be understood in terms of Kondo-like physics due to the development of a double-well structure in the effective potential for the ions.
Meyer
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D
Department of Mathematics, Imperial College, London SW7 2BZ, United Kingdom. d.meyer@ic.ac.uk
Hewson
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Bulla
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