A general quantum algorithm for open quantum dynamics demonstrated with the Fenna-Matthews-Olson complex

Zixuan Hu1, Kade Head-Marsden2, David A. Mazziotti3, Prineha Narang2, and Sabre Kais1

1Department of Chemistry, Department of Physics, and Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, IN 47907, USA
2John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
3Department of Chemistry and The James Franck Institute, The University of Chicago, Chicago, IL 60637 USA

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Using quantum algorithms to simulate complex physical processes and correlations in quantum matter has been a major direction of quantum computing research, towards the promise of a quantum advantage over classical approaches. In this work we develop a generalized quantum algorithm to simulate any dynamical process represented by either the operator sum representation or the Lindblad master equation. We then demonstrate the quantum algorithm by simulating the dynamics of the Fenna-Matthews-Olson (FMO) complex on the IBM QASM quantum simulator. This work represents a first demonstration of a quantum algorithm for open quantum dynamics with a moderately sophisticated dynamical process involving a realistic biological structure. We discuss the complexity of the quantum algorithm relative to the classical method for the same purpose, presenting a decisive query complexity advantage of the quantum approach based on the unique property of quantum measurement.

Open quantum dynamics is an important subfield of quantum physics that studies the time evolution of a system interacting with an environment. Although numerous quantum algorithms have been developed to simulate quantum systems, so far few studies have been done to simulate open quantum dynamics despite its importance. In this work we develop a generalized quantum algorithm for open quantum dynamics and simulate the Fenna-Matthews-Olson complex on the IBM quantum simulator. This is so far as we know the first quantum simulator demonstration of using a quantum algorithm to simulate such a complex dynamical model.

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