Pauli crystal melting in shaken optical traps

TL;DR

This paper investigates how Pauli crystals in trapped fermionic systems melt under periodic shaking, revealing that trap imperfections and geometry, rather than energy increase, drive the melting process.

Contribution

It demonstrates that melting of Pauli crystals is influenced by trap imperfections and Floquet mode population, not just energy, providing new insights into their dynamics.

Findings

Melting occurs only with trap imperfections and sufficient shaking amplitude.

Trap geometry and Floquet modes are key factors in melting.

Melting is not solely due to energy increase.

Abstract

Pauli crystals are ordered geometric structures that emerge in trapped noninteracting fermionic systems due to their underlying Pauli repulsion. The deformation of Pauli crystals - often called melting - has been recently observed in experiments, but the mechanism that leads to it remains unclear. We address this question by studying the melting dynamics of N=6 fermions as a function of periodic driving and experimental imperfections in the trap (anisotropy and anharmonicity) by employing a combination of numerical simulations and Floquet theory. Surprisingly, we reveal that the melting of Pauli crystals is not simply a direct consequence of an increase in system energy, but is instead related to the trap geometry and the population of the Floquet modes. We show that the melting is absent in traps without imperfections and triggered only by a sufficiently large shaking amplitude in traps with imperfections.