Magnetic field induced non-Gaussian fluctuations in macroscopic equilibrium systems

TL;DR

This paper investigates how magnetic fields induce non-Gaussian fluctuations in macroscopic equilibrium systems, revealing a nonzero third cumulant of current related to spectral density and current derivatives, serving as a test for fluctuation relations.

Contribution

It demonstrates that magnetic fields can induce non-Gaussian current fluctuations in macroscopic systems, extending fluctuation relation tests beyond quantum-coherent regimes.

Findings

Magnetic field induces a nonzero third cumulant of current at equilibrium.

The third cumulant relates to voltage derivatives of spectral density and current.

The system offers a robust test of non-equilibrium fluctuation relations.

Abstract

We calculate the magnetic-field dependent nonlinear conductance and noise in a macroscopic inhomogeneous system. If the system does not possess a specific symmetry, the magnetic field induces a nonzero third cumulant of the current even at equilibrium. This cumulant is related to the first and second voltage derivatives of the spectral density and average current in the same way as for mesoscopic quantum-coherent systems. The system provides a robust test of a non-equilibrium fluctuation relation.