Realizing the Hayden-Preskill Protocol with Coupled Dicke Models

TL;DR

This paper proposes a physical realization of the Hayden-Preskill protocol using coupled Dicke models with thermofield double states, enabling information recovery from scrambled quantum systems in a realistic setup.

Contribution

It introduces a novel implementation of the Hayden-Preskill protocol with Dicke models and demonstrates optimal information readout in the most chaotic regime.

Findings

Maximum readout efficiency at the system's most chaotic point

Shorter scrambling time correlates with higher decoding success

Feasibility of studying black hole information paradox in laboratory settings

Abstract

Hayden and Preskill proposed a thought experiment that Bob can recover the information Alice throws into a black hole if he has a quantum computer entangled with the black hole, and Yoshida and Kitaev recently proposed a concrete decoding scheme. The parallel question is that after a small system is thermalized with a large system, how one can decode the initial state information with the help of two entangled many-body systems. Here we propose to realize this protocol in a physical system of two Dicke models, with two cavity fields prepared in a thermofield double state. We show that the Yoshida-Kitaev protocol allows us to read out the initial spin information after it is scrambled into the cavity. We show that the readout efficiency reaches a maximum when the model parameter is tuned to the regime where the system is the most chaotic, characterized by the shortest scrambling time in the out-of-time-ordered correlation function. Our proposal opens up the possibility of discussing this profound thought experiment in a realistic setting.