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Title: Variational Quantum Fidelity Estimation

Abstract

Computing quantum state fidelity will be important to verify and characterize states prepared on a quantum computer. In this work, we propose novel lower and upper bounds for the fidelity F ( ρ , σ ) based on the ``truncated fidelity'' F ( ρ m , σ ) , which is evaluated for a state ρ m obtained by projecting ρ onto its m -largest eigenvalues. Our bounds can be refined, i.e., they tighten monotonically with m . To compute our bounds, we introduce a hybrid quantum-classical algorithm, called Variational Quantum Fidelity Estimation, that involves three steps: (1) variationally diagonalize ρ , (2) compute matrix elements of σ in the eigenbasis of ρ , and (3) combine these matrix elements to compute our bounds. Our algorithm is aimed at the case where σ is arbitrary and more » ρ is low rank, which we call low-rank fidelity estimation, and we prove that no classical algorithm can efficiently solve this problem under reasonable assumptions. Finally, we demonstrate that our bounds can detect quantum phase transitions and are often tighter than previously known computable bounds for realistic situations.« less

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [1]; ORCiD logo [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. California Institute of Technology (CalTech), Pasadena, CA (United States)
Publication Date:
Research Org.:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division; US Air Force Office of Scientific Research (AFOSR); National Science Foundation (NSF)
OSTI Identifier:
1659189
Report Number(s):
LA-UR-19-25585
Journal ID: ISSN 2521-327X
Grant/Contract Number:  
89233218CNA000001; A9550-16-1-0495; PHY-1733907
Resource Type:
Accepted Manuscript
Journal Name:
Quantum
Additional Journal Information:
Journal Volume: 4; Journal ID: ISSN 2521-327X
Publisher:
Quantum Science Open Community
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING; Mathematics; Quantum; Algorithm; Fidelity; Variational; Computing

Citation Formats

Cerezo de la Roca, Marco Vinicio Sebastian, Poremba, Alexander, Cincio, Lukasz, and Coles, Patrick Joseph. Variational Quantum Fidelity Estimation. United States: N. p., 2020. Web. doi:10.22331/q-2020-03-26-248.
Cerezo de la Roca, Marco Vinicio Sebastian, Poremba, Alexander, Cincio, Lukasz, & Coles, Patrick Joseph. Variational Quantum Fidelity Estimation. United States. https://doi.org/10.22331/q-2020-03-26-248
Cerezo de la Roca, Marco Vinicio Sebastian, Poremba, Alexander, Cincio, Lukasz, and Coles, Patrick Joseph. Thu . "Variational Quantum Fidelity Estimation". United States. https://doi.org/10.22331/q-2020-03-26-248. https://www.osti.gov/servlets/purl/1659189.
@article{osti_1659189,
title = {Variational Quantum Fidelity Estimation},
author = {Cerezo de la Roca, Marco Vinicio Sebastian and Poremba, Alexander and Cincio, Lukasz and Coles, Patrick Joseph},
abstractNote = {Computing quantum state fidelity will be important to verify and characterize states prepared on a quantum computer. In this work, we propose novel lower and upper bounds for the fidelity F(ρ,σ) based on the ``truncated fidelity'' F(ρm,σ), which is evaluated for a state ρm obtained by projecting ρ onto its m-largest eigenvalues. Our bounds can be refined, i.e., they tighten monotonically with m. To compute our bounds, we introduce a hybrid quantum-classical algorithm, called Variational Quantum Fidelity Estimation, that involves three steps: (1) variationally diagonalize ρ, (2) compute matrix elements of σ in the eigenbasis of ρ, and (3) combine these matrix elements to compute our bounds. Our algorithm is aimed at the case where σ is arbitrary and ρ is low rank, which we call low-rank fidelity estimation, and we prove that no classical algorithm can efficiently solve this problem under reasonable assumptions. Finally, we demonstrate that our bounds can detect quantum phase transitions and are often tighter than previously known computable bounds for realistic situations.},
doi = {10.22331/q-2020-03-26-248},
journal = {Quantum},
number = ,
volume = 4,
place = {United States},
year = {Thu Mar 26 00:00:00 EDT 2020},
month = {Thu Mar 26 00:00:00 EDT 2020}
}

Works referenced in this record:

Using Quantum Computers for Quantum Simulation
text, January 2010


Exact Ising model simulation on a quantum computer
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swap test and Hong-Ou-Mandel effect are equivalent
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Quantum fidelity and thermal phase transitions
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The “transition probability” in the state space of a ∗-algebra
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  • Brun, T. A.
  • Quantum Information and Computation, Vol. 4, Issue 5
  • DOI: 10.26421/QIC4.5-6

Works referencing / citing this record:

Reformulation of the No-Free-Lunch Theorem for Entangled Data Sets
text, January 2020


Quantum Algorithm for Fidelity Estimation
text, January 2021


Variational quantum Gibbs state preparation with a truncated Taylor series
text, January 2020


Variational quantum algorithm for estimating the quantum Fisher information
journal, February 2022


Variational quantum algorithms
journal, August 2021