Holographic quenches and anomalous transport

TL;DR

This paper investigates the holographic response of the chiral magnetic effect to time-dependent electric fields, revealing universal quench behaviors, resonance phenomena, and long-lived currents linked to anomalies.

Contribution

It introduces a detailed holographic analysis of chiral anomaly-induced transport under quenches, including resonance effects and the dynamics of quasi-normal modes.

Findings

Identification of universal 'fast' quench response behavior.

Discovery of Landau level resonances in conductivity.

Observation of long-lived AC currents due to anomalies.

Abstract

We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e.,~residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. We show that the existence of these resonances induces, among others, a long-lived AC electric current once the electric field is switched off.