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Title: Single-ancilla ground state preparation via Lindbladians
We design a quantum algorithm for ground state preparation in the early fault tolerant regime. As a Monte Carlo style quantum algorithm, our method features a Lindbladian where the target state is stationary. The construction of this Lindbladian is algorithmic and should not be seen as a specific approximation to some weakly coupled system-bath dynamics in nature. Our algorithm can be implemented using just one ancilla qubit and efficiently simulated on a quantum computer. It can prepare the ground state even when the initial state has zero overlap with the ground state, bypassing the most significant limitation of methods like quantum phase estimation. As a variant, we also propose a discrete-time algorithm, demonstrating even better efficiency and providing a near-optimal simulation cost depending on the desired evolution time and precision. Numerical simulations using Ising and Hubbard models demonstrate the efficacy and applicability of our method. Published by the American Physical Society2024  more » « less
Award ID(s):
2016245
PAR ID:
10589676
Author(s) / Creator(s):
; ;
Publisher / Repository:
APS/Physical Review Journals
Date Published:
Journal Name:
Physical Review Research
Volume:
6
Issue:
3
ISSN:
2643-1564
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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