Engineering subharmonic responses beyond prethermalization via Floquet scar states

Abstract

In this work we propose a new scheme to engineer subharmonic responses via scar states in a generalized PXP model. We first show that the generalized PXP model also possesses a band of scar states like the pristine PXP model does. In addition, we reveal that a generalized forward scattering approximation (FSA) still works for these scar states. We further argue that the FSA subspace exhibits an $SO(3)$ symmetry, which enables an $SO(3)$-FSA approach for the scar states. When such a model is placed under periodic driving, nontrivial Floquet scar states emerge in the quasienergy spectrum. One appealing feature of such Floquet scar states is that they can support subharmonic responses akin to the discrete time crystalline phase. In particular, such subharmonic responses can exist beyond the conventional prethermalization regime, where either large frequencies or large driving amplitudes are required.

5 pages, 4 figures. Comments are welcome

References in corpus (10)

• Thermalization and its mechanism for generic isolated quantum systems
• Probing many-body dynamics on a 51-atom quantum simulator
• Many body localization and thermalization in quantum statistical mechanics
• Emergent SU(2) dynamics and perfect quantum many-body scars
• Observation of a many-body-localized discrete time crystal with a programmable spin-based quantum simulator
• Dynamics of the vacuum state in a periodically driven Rydberg chain
• Driving quantum many-body scars in the PXP model
• Discrete time crystals enforced by Floquet-Bloch scars
• Constructing quantum many-body scar Hamiltonians from Floquet automata
• Leveraging static quantum many-body scars into period-doubled responses

Cited by in corpus (2)

• Controlling nonergodicity in quantum many-body systems by reinforcement learning
• Prethermalization in the PXP Model under Continuous Quasiperiodic Driving