arXiv:2005.00029 · Physical Review Research

Capturing non-Markovian dynamics on near-term quantum computers

Kade Head-Marsden, Stefan Krastanov, David A. Mazziotti, Prineha Narang

Published Feb 25, 2021• 72 citations

Abstract

With the rapid progress in quantum hardware, there has been an increased interest in new quantum algorithms to describe complex many-body systems searching for the still-elusive goal of "useful quantum advantage."Surprisingly, quantum algorithms for the treatment of open quantum systems (OQSs) have remained underexplored, in part due to the inherent challenges of mapping non-unitary evolution into the framework of unitary gates.Evolving an open system unitarily necessitates dilation into a new effective system to incorporate critical environmental degrees of freedom.In this context, we present and validate a new quantum algorithm to treat non-Markovian dynamics in OQSs built on the ensemble of Lindblad's trajectories approach, invoking the Sz.-Nagy dilation theorem.Here we demonstrate our algorithm on the Jaynes-Cummings model in the strong-coupling and detuned regimes, relevant in quantum optics and driven quantum system studies.This algorithm, a key step towards generalized modeling of non-Markovian dynamics on a noisy-quantum device, captures a broad class of dynamics and opens up a new direction in OQS problems.

DOI: 10.1103/physrevresearch.3.013182

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