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arXiv · 1909.08640

Variational Quantum Simulation of Ultrastrong Light-Matter Coupling

Agustin Di Paolo·Panagiotis Kl. Barkoutsos·Ivano Tavernelli·Alexandre Blais
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Abstract

We propose the simulation of quantum-optical systems in the ultrastrong-coupling regime using a variational quantum algorithm. More precisely, we introduce a short-depth variational form to prepare the groundstate of the multimode Dicke model on a quantum processor and present proof-of-principle results obtained via cloud access to an IBM device. We moreover provide an algorithm for characterizing the groundstate by Wigner state tomography. Our work is a first step towards digital quantum simulation of quantum-optical systems with potential applications to the spin-boson, Kondo and Jahn-Teller models.

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Agustin Di Paolo, Panagiotis Kl. Barkoutsos, Ivano Tavernelli, Alexandre Blais. 2019-09-18. Variational Quantum Simulation of Ultrastrong Light-Matter Coupling. https://doi.org/10.1103/physrevresearch.2.033364

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