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arXiv · 2412.19590

Robust phase estimation of the ground-state energy without controlled time evolution on a quantum device

Hiroki Kuji·Yuta Shingu·Tetsuro Nikuni·Takashi Imoto·Kenji Sugisaki·Yuichiro Matsuzaki
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Abstract

Estimating the ground-state energy of Hamiltonians in quantum systems is an important task. In this work, we demonstrate that the ground-state energy can be accurately estimated without controlled time evolution by using adiabatic state preparation (ASP) and Ramsey-type measurement. By considering the symmetry of the Hamiltonian governing the time evolution during ASP, we can prepare a superposition of the ground state and reference state whose eigenvalue is known. This enables the estimation of the ground-state energy via Ramsey-type measurement. Furthermore, our method is robust against non-adiabatic transitions, making it suitable for use with early fault-tolerant quantum computers and quantum annealing.

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Hiroki Kuji, Yuta Shingu, Tetsuro Nikuni, Takashi Imoto, Kenji Sugisaki, Yuichiro Matsuzaki. 2024-12-27. Robust phase estimation of the ground-state energy without controlled time evolution on a quantum device. https://doi.org/10.1103/physreva.111.042618

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