Subharmonics and Aperiodicity in Hysteresis Loops

TL;DR

This paper demonstrates that hysteresis loops in certain magnetic systems can be aperiodic and involve multiple cycles before returning to the initial state, especially in large disordered systems like spin glasses.

Contribution

It introduces the concept of subharmonic and aperiodic hysteresis loops in spin glasses, showing these phenomena can occur in large, disordered magnetic systems.

Findings

Hysteresis loops can be aperiodic in large spin glasses.

Multiple cycles are needed for the system to return to initial state.

Aperiodicity increases with system size.

Abstract

We show that it is possible to have hysteretic behavior for magnets that does not form simple closed loops in steady state, but must cycle multiple times before returning to its initial state. We show this by studying the zero-temperature dynamics of the 3d Edwards Anderson spin glass. The specific multiple varies from system to system and is often quite large and increases with system size. The last result suggests that the magnetization could be aperiodic in the large system limit for some realizations of randomness. It should be possible to observe this phenomena in low-temperature experiments.