Abstract An explicit analytical expression is derived for the ground state energy of a linearized polaron model in a constant and uniform magnetic field. In this model, the validity of the Feynman inequality in a magnetic field is investigated. In a fixed magnetic field, it is shown that even for arbitrarily small electron—phonon coupling, the presence of a magnetic field is prohibitive for the application of the Feynman inequality.

physica status solidi (b)Feb 1, 198811 citations

arXiv:cond-mat/0602050 · Solid State Communications

On the ground state energy of a gas of interacting polarons in a magnetic field

Katrijn Putteneers, F. Brosens, Serghei N. Klimin, J. T. Devreese

Published Apr 14, 2005• 5 citations

arXiv HTML PDF

DOI: 10.1016/j.ssc.2005.03.050

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physica status solidi (b)Feb 1, 198811 citations

The ground-state energy of an

N

-polaron system confined to a quantum dot with a neutralizing background charge is investigated within an all-coupling many-body path-integral variational principle taking into account both Fermi statistics of polarons and the electron-electron interaction. The treatment of the ground-state energy is performed for both closed- and open-shell systems. The average fermion density in the neutral spherical dot is characterized by the Wigner-Seitz parameter

{r}_{s}

. For a sufficiently large but finite number of polarons, the dependency of the ground-state energy on

{r}_{s}

is very similar to that for a polaron gas in bulk. From this, we can conclude that the ground-state energy of a polaron gas in bulk can be qualitatively described using a model of a finite number of polarons in a confinement potential provided by a neutralizing background charge.