Prethermalization in quenched spinor condensates

TL;DR

This paper investigates the non-thermalizing dynamics of quenched spinor condensates, demonstrating the existence of a prethermalized state and analyzing the limitations of Bogoliubov theory through the Truncated Wigner Approximation.

Contribution

It introduces a comprehensive analysis of spinor condensate dynamics post-quench, highlighting the persistence of prethermalization and the failure of thermalization over long times.

Findings

System reaches a prethermalized state without thermalizing.

Bogoliubov theory fails to predict long-time correlations.

Landau damping rates support the non-thermalization conclusion.

Abstract

Motivated by recent experiments, we consider the dynamics of spin-one spinor condensates after a quantum quench from the polar to ferromagnetic state from varying the quadratic Zeeman field q. We apply the Truncated Wigner Approximation (TWA) to the spinor system, including all spatial and spin degrees of freedom. For short times, we find full agreement with the linearized Bogoliubov analysis. For longer times, where the Bogoliubov theory fails, we find that the system reaches a quasi-steady prethermalized state. We compute the Bogoliubov spectrum about the ferromagnetic state with general q and show that the resulting finite temperature correlation functions grossly disagree with the full TWA results, thus indicating that the system does not thermalize even over very long time scales. Finally we show that the absence of thermalization over realistic time scales is consistent with calculations of Landau damping rates of excitations in the finite-temperature condensate.