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Well-defined quasiparticles in interacting metallic grains

Dominique Gobert·Moshe Schechter·Ulrich Schollwock·Jan von Delft
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Abstract

We analyze spectral functions of mesoscopic systems with large dimensionless conductance, which can be described by a universal Hamiltonian. We show that an important class of spectral functions are dominated by one single state only, which implies the existence of well-defined (i.e. infinite-lifetime) quasiparticles. Furthermore, the dominance of a single state enables us to calculate zero-temperature spectral functions with high accuracy using the density-matrix renormalization group. We illustrate the use of this method by calculating the tunneling density of states of metallic grains and the magnetic response of mesoscopic rings.

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Dominique Gobert, Moshe Schechter, Ulrich Schollwock, Jan von Delft. 2004-04-26. Well-defined quasiparticles in interacting metallic grains. https://doi.org/10.1103/physrevlett.93.186402

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