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arXiv · 2203.00658

Quantum many-body scars in bipartite Rydberg arrays originate from hidden projector embedding

Keita Omiya·Markus Müller
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Abstract

We study the nature of the ergodicity-breaking "quantum many-body scar" states that appear in the PXP model describing constrained Rabi oscillations. For a {wide class of bipartite lattices} of Rydberg atoms, we reveal that the nearly energy-equidistant tower of these states arises from the Hamiltonian's close proximity to a generalized projector-embedding form, a structure common to many models hosting quantum many-body scars. We construct a non-Hermitian, but strictly local extension of the PXP model hosting exact quantum scars, and show how various Hermitian scar-stabilizing extensions from the literature can be naturally understood within this framework. The exact scar states are obtained analytically as large spin states of explicitly constructed pseudospins. The quasi-periodic motion ensuing from the N\'eel state is finally shown to be the projection onto the Rydberg-constrained subspace of the precession of the large pseudospin.

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Keita Omiya, Markus Müller. 2022-03-01. Quantum many-body scars in bipartite Rydberg arrays originate from hidden projector embedding. https://doi.org/10.1103/physreva.107.023318

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