ModMax Electrodynamics and Holographic Magnetotransport

TL;DR

This paper explores how ModMax nonlinear electrodynamics affects magnetotransport properties in a holographic model, revealing modifications to conductivities and signals relevant to high-temperature superconductors.

Contribution

It introduces a holographic framework coupling ModMax electrodynamics with gravity, analyzing nonlinear effects on charge transport and magnetotransport in strongly coupled systems.

Findings

ModMax parameter alters Hall and Nernst signals.

Reproduces high-$T_c$ cuprate features like superconducting dome.

Identifies exotic quasiparticle-dominated states in nonlinear regime.

Abstract

We study magnetotransport in a holographic model where ModMax nonlinear electrodynamics is coupled to Einstein anti--de Sitter gravity. To incorporate momentum relaxation, we introduce spatially linear free scalar fields that break translational symmetry, resulting in an anisotropic medium. Using linear response theory, we compute the DC conductivity matrix in the presence of an external magnetic field, expressing the conductivities in terms of horizon data. Our results demonstrate how the nonlinear ModMax parameter modifies charge transport, particularly influencing the Hall angle and Nernst signal. The nonlinear corrections introduce distinct deviations in both longitudinal and Hall conductivities while preserving the characteristic temperature scaling of strange metals, offering new insights into strongly coupled systems with nonlinear electromagnetic interactions. Notably, the Nernst signal reproduces that of high-$T_c$ cuprate superconductors showing a superconducting dome and a normal phase, with the ModMax deformation parameter tuning critical and onset temperatures. In the strongly nonlinear regime, we find evidence of an exotic state dominated by quasiparticle excitations in the dual material.