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arXiv · 2205.09491

Quantum associative memory with a single driven-dissipative nonlinear oscillator

Adrià Labay-Mora·Roberta Zambrini·Gian Luca Giorgi
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Abstract

Algorithms for associative memory typically rely on a network of many connected units. The prototypical example is the Hopfield model, whose generalizations to the quantum realm are mainly based on open quantum Ising models. We propose a realization of associative memory with a single driven-dissipative quantum oscillator exploiting its infinite degrees of freedom in phase space. The model can improve the storage capacity of discrete neuron-based systems in a large regime and we prove successful state discrimination between $n$ coherent states, which represent the stored patterns of the system. These can be tuned continuously by modifying the driving strength, constituting a modified learning rule. We show that the associative-memory capacity is inherently related to the existence of a spectral gap in the Liouvillian superoperator, which results in a large timescale separation in the dynamics corresponding to a metastable phase.

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Adrià Labay-Mora, Roberta Zambrini, Gian Luca Giorgi. 2023-05-16. Quantum associative memory with a single driven-dissipative nonlinear oscillator. https://doi.org/10.1103/physrevlett.130.190602

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