Deviations from generalized Equipartition in Confined, Laser Cooled Atoms

TL;DR

This study demonstrates a significant deviation from the classical equipartition theorem in laser-cooled, confined atoms, revealing non-thermal behavior and inhomogeneous energy distribution, supported by experiments, simulations, and analytical analysis.

Contribution

The paper provides the first experimental measurement and analysis of deviations from equipartition in confined, laser-cooled atoms, highlighting non-thermal states and their dynamics.

Findings

Deviations from equipartition grow with anomalous system dynamics.

Inhomogeneous kinetic energy distribution observed experimentally.

Numerical simulations and analytical analysis support experimental results.

Abstract

We observe a significant steady-state deviation from the generalized equipartition theorem, one of the pivotal results of classical statistical mechanics, in a system of confined, laser cooled atoms. We quantify this deviation, measure its dynamics and show that its steady state value quantifies the departure of non-thermal states from thermal equilibrium even for anharmonic confinement. In particular, we find that deviations from equipartition grow as the system dynamics becomes more anomalous. We present numerical simulations that validate the experimental data and reveal an inhomogeneous distribution of the kinetic energy through the system, supported by an analytical analysis of the phase space.m, supported by an analytical analysis of the phase space.