Geometric phase in external electromagnetic fields

TL;DR

This paper introduces a generalized scalar Berry phase, called the macroscopic rotonic field, which describes the interaction of electronic systems with external electromagnetic fields, extending previous polarization-based approaches.

Contribution

It proposes a new vector field, the macroscopic rotonic field, as a more general framework for understanding Berry phases in electronic systems under electromagnetic influence.

Findings

Defined the macroscopic rotonic field as a new scalar Berry phase

Connected polarization variations to a flux of the rotonic field

Extended the concept of Berry phase to broader electromagnetic interactions

Abstract

Variations of polarization of the electronic field is a dielectric property quantified by Resta et al. and discovered to be a Berry phase of the electronic subsystem. In order to continue the previous research we wrote a scalar phase \Phi as the circulation of the polarization field or in alternative and in a more general form as the flux of a new vector field called macroscopic rotonic field. The latter shows to be a more general scalar Berry phase concerning the interaction of the electronic subsystem with an external electromagnetic field.