Signatures of Associative Memory Behavior in a Multimode Dicke Model

Eliana Fiorelli, Matteo Marcuzzi, Pietro Rotondo, Federico Carollo, and Igor Lesanovsky
Phys. Rev. Lett. 125, 070604 – Published 12 August 2020
PDFHTMLExport Citation

Abstract

Dicke-like models can describe a variety of physical systems, such as atoms in a cavity or vibrating ion chains. In equilibrium these systems often feature a radical change in their behavior when switching from weak to strong spin-boson interaction. This usually manifests in a transition from a “dark” to a “superradiant” phase. However, understanding the out-of-equilibrium physics of these models is extremely challenging, and even more so for strong spin-boson coupling. Here we show that the nonequilibrium strongly interacting multimode Dicke model can mimic some fundamental properties of an associative memory—a system which permits the recognition of patterns, such as letters of an alphabet. Patterns are encoded in the couplings between spins and bosons, and we discuss the dynamics of the spins from the perspective of pattern retrieval in associative memory models. We identify two phases, a “paramagnetic” and a “ferromagnetic” one, and a crossover behavior between these regimes. The “ferromagnetic” phase is reminiscent of pattern retrieval. We highlight similarities and differences with the thermal dynamics of a Hopfield associative memory and show that indeed elements of “machine learning behavior” emerge in the strongly coupled multimode Dicke model.

  • Figure
  • Figure
  • Received 18 March 2020
  • Accepted 17 July 2020

DOI:https://doi.org/10.1103/PhysRevLett.125.070604

© 2020 American Physical Society

Physics Subject Headings (PhySH)

Statistical Physics & Thermodynamics

Authors & Affiliations

Eliana Fiorelli1,2, Matteo Marcuzzi1,2, Pietro Rotondo3, Federico Carollo4, and Igor Lesanovsky1,2,4

  • 1School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, United Kingdom
  • 2Centre for the Mathematics and Theoretical Physics of Quantum Non-equilibrium Systems, University of Nottingham, Nottingham NG7 2RD, United Kingdom
  • 3INFN, Sezione di Milano, via Celoria 16, 20100 Milano, Italy
  • 4Institut für Theoretische Physik, Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 125, Iss. 7 — 14 August 2020

Reuse & Permissions
Access Options

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×