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DOE OSTI · 1868165

Imaginary Time Propagation on a Quantum Chip

Turro, Francesco·Amitrano, V.·Luchi, P.·Roggero, A.·Wendt, K. A.·DuBois, J. L.·Quaglioni, S.·Pederiva, F.
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Abstract

We report evolution in imaginary time is a prominent technique for finding the ground state of quantum many-body systems, and the heart of a number of numerical methods that have been used with great success in quantum chemistry, condensed matter, and nuclear physics. We propose an algorithm to implement imaginary time propagation on a quantum computer. Our algorithm is devised in the context of an efficient encoding into an optimized gate, drawing on the underlying characteristics of the quantum device of a unitary operation in an extended Hilbert space. However, we prove that for simple problems it can also be successfully applied to standard digital quantum machines. This work paves the way for porting quantum many-body methods based on imaginary-time propagation to near-term quantum devices, enabling the future quantum simulation of the ground states of a broad class of microscopic systems.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSquantum algorithmsquantum computationquantum simulation

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BibTeXRIS

Turro, Francesco, Amitrano, V., Luchi, P., Roggero, A., Wendt, K. A., DuBois, J. L., Quaglioni, S., Pederiva, F.. 2022-02-28. Imaginary Time Propagation on a Quantum Chip. https://doi.org/10.1103/physreva.105.022440

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