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arXiv · 1501.05660

Dynamical Stability of a Many-body Kapitza Pendulum

Roberta Citro·Emanuele G. Dalla Torre·Luca DÁlessio·Anatoli Polkovnikov·Mehrtash Babadi·Takashi Oka·Eugene Demler
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Abstract

We consider a many-body generalization of the Kapitza pendulum: the periodically-driven sine-Gordon model. We show that this interacting system is dynamically stable to periodic drives with finite frequency and amplitude. This finding is in contrast to the common belief that periodically-driven unbounded interacting systems should always tend to an absorbing infinite-temperature state. The transition to an unstable absorbing state is described by a change in the sign of the kinetic term in the effective Floquet Hamiltonian and controlled by the short-wavelength degrees of freedom. We investigate the stability phase diagram through an analytic high-frequency expansion, a self-consistent variational approach, and a numeric semiclassical calculations. Classical and quantum experiments are proposed to verify the validity of our results.

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Roberta Citro, Emanuele G. Dalla Torre, Luca DÁlessio, Anatoli Polkovnikov, Mehrtash Babadi, Takashi Oka, Eugene Demler. 2015-01-22. Dynamical Stability of a Many-body Kapitza Pendulum. https://doi.org/10.1016/j.aop.2015.03.027

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