Hypergrid subgraphs and the origin of scarred quantum walks in the
many-body Hilbert space
- URL: http://arxiv.org/abs/2112.06885v3
- Date: Fri, 24 Jun 2022 16:55:43 GMT
- Title: Hypergrid subgraphs and the origin of scarred quantum walks in the
many-body Hilbert space
- Authors: Jean-Yves Desaules, Kieran Bull, Aiden Daniel, and Zlatko Papi\'c
- Abstract summary: We explore the origin of scarred wavefunction revivals in a family of models obtained by deforming the graph adjacency matrix of the PXP model.
We argue that the model of two joined hypercubes captures the essential features of many-body scarring present in the PXP model.
Our results shed light on the nature of scarring in the PXP model by identifying its simple parent model, while also highlighting its distinction from the free-spin precession.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Following the recent observation of wave function revivals in large Rydberg
atom quantum simulators, much effort has focused on understanding the emergence
of many-body scars in non-integrable quantum systems. Here we explore the
origin of scarred wavefunction revivals in a family of models obtained by
deforming the graph adjacency matrix of the PXP model - the effective model of
Rydberg atoms in the strong Rydberg blockade regime. We consider deformations
that either enhance the Rydberg constraint, ultimately resulting in an
effective tight-binding model of two hypercubes joined at a single vertex, or
relax the constraint until reaching the free spin-1/2 model. In the former
case, we argue that the model of two joined hypercubes captures the essential
features of many-body scarring present in the PXP model. On the other hand,
relaxing the constraint leads to a sequence of new scarred models, some with
more robust scarring signatures than the PXP model, as can be understood from
the graph-theoretic viewpoint. Our results shed light on the nature of scarring
in the PXP model by identifying its simple parent model, while also
highlighting its distinction from the free-spin precession.
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