Nonminimal planar electrodynamics modified by higher-derivative terms

TL;DR

This paper develops a (2+1)-dimensional modified electrodynamics framework with higher-derivative terms, analyzing its physical modes, unitarity, and potential applications to condensed matter phenomena like the quantum Hall effect.

Contribution

It introduces a novel class of nonminimal planar electrodynamics with higher derivatives inspired by the SME, exploring their physical properties and potential condensed matter applications.

Findings

Derived propagators and physical modes for the models.

Identified parameter regions for sub- and superluminal propagation.

Predicted momentum- and direction-dependent Hall resistivity corrections.

Abstract

We consider a (2+1)-dimensional modified electrodynamics endowed with terms that are either Lorentz-invariant or Lorentz-violating and involve an ever increasing number of derivatives. Our construction relies on U(1) gauge invariance and the Abelian Chern-Simons term poses the starting point. The structure of the nonminimal Standard-Model Extension (SME) in (3+1) spacetime dimensions serves as an inspiration for our pursuit. For elaborate studies and applications we particularly focus on the second term of the operator series in the general framework, which is the first contribution with additional derivatives. The latter forms the essential ingredient for several models of modified planar electrodynamics to be examined. The propagators of the models constitute the foundation for us deriving the physical propagating modes as well as for drawing conclusions on unitarity in the quantum regime. We are also interested in identifying parameter regions of sub- and superluminal mode propagation and determine classical solutions of the field equations for the planar models introduced. Moreover, a duality between an extended Chern-Simons theory and a subset of the fermion sector coefficients in the nonminimal SME is pointed out, as well. Finally, the integer quantum Hall effect is chosen as a testbed to demonstrate the applicability of our findings to real physical systems. Predictions on momentum- and direction-dependent corrections of the Hall resistivity are made at the level of effective field theory, which could be tested in experiments. Thus, the (2+1)-dimensional models proposed are potentially applicable to model electromagnetic phenomena in certain planar condensed-matter systems.