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arXiv · 0904.2172

Exotic Freezing of Response in Quantum Many-Body System

Abstract

We show that when a quantum many-body system is subjected to coherent periodic driving, the response may exhibit exotic freezing behavior in high driving frequency ($ω$) regime. In a periodically driven classical thermodynamic system, freezing at high $ω$ occurs when $1/ω$ is much smaller than the characteristic relaxation time of the system, and hence the freezing always increases there as $ω$ is increased. Here, in the contrary, we see surprising non-monotonic freezing behavior of the response with $ω$, showing curious peak-valley structure. Quite interestingly, the entire system tends to freeze almost absolutely (the freezing peaks) when driven with a certain combination of driving parameters values (amplitude and $ω$) due to coherent suppression of dynamics of the quantum many-body modes, which has no classical analog. We demonstrate this new freezing phenomenon analytically (supported by large-scale numerics) for a general class of integrable quantum spin systems.

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BibTeXRIS

Arnab Das. 2010-11-01. Exotic Freezing of Response in Quantum Many-Body System. https://doi.org/10.1103/physrevb.82.172402

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