Asymptotic series for low-energy excitations of the Fr\"ohlich Polaron at strong coupling

TL;DR

This paper develops an asymptotic series for the low-energy eigenvalues of the confined Fröhlich polaron at strong coupling, using a two-fold perturbation approach involving the electron Pekar minimizer and quantum field excitations.

Contribution

It introduces a novel asymptotic series for the polaron's low-energy spectrum at strong coupling, combining electron and field perturbations.

Findings

Derived explicit coefficients for the asymptotic series.

Established the validity of the series in the strong coupling regime.

Provided a new analytical tool for studying polaron excitations.

Abstract

We consider the confined Fr\"ohlich polaron and establish an asymptotic series for the low-energy eigenvalues in negative powers of the coupling constant. The coefficients of the series are derived through a two-fold perturbation approach, involving expansions around the electron Pekar minimizer and the excitations of the quantum field.