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arXiv · 2106.12588

Quantum Simulation of Open Quantum Systems Using a Unitary Decomposition of Operators

Anthony W. Schlimgen·Kade Head-Marsden·LeeAnn M. Sager·Prineha Narang·David A. Mazziotti
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Abstract

Electron transport in realistic physical and chemical systems often involves the non-trivial exchange of energy with a large environment, requiring the definition and treatment of open quantum systems. Because the time evolution of an open quantum system employs a non-unitary operator, the simulation of open quantum systems presents a challenge for universal quantum computers constructed from only unitary operators or gates. Here we present a general algorithm for implementing the action of any non-unitary operator on an arbitrary state on a quantum device. We show that any quantum operator can be exactly decomposed as a linear combination of at most four unitary operators. We demonstrate this method on a two-level system in both zero and finite temperature amplitude damping channels. The results are in agreement with classical calculations, showing promise in simulating non-unitary operations on intermediate-term and future quantum devices.

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Anthony W. Schlimgen, Kade Head-Marsden, LeeAnn M. Sager, Prineha Narang, David A. Mazziotti. 2021-06-23. Quantum Simulation of Open Quantum Systems Using a Unitary Decomposition of Operators. https://doi.org/10.1103/physrevlett.127.270503

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