Best-approximation error for parametric quantum circuits

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Funcke, Lena, Hartung, Tobias, Jansen, Karl, Kühn, Stefan, Schneider, Manuel, Stornati, Paolo
Format: Preprint
Veröffentlicht: 2021
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866911507026018304
author Funcke, Lena
Hartung, Tobias
Jansen, Karl
Kühn, Stefan
Schneider, Manuel
Stornati, Paolo
author_facet Funcke, Lena
Hartung, Tobias
Jansen, Karl
Kühn, Stefan
Schneider, Manuel
Stornati, Paolo
contents In Variational Quantum Simulations, the construction of a suitable parametric quantum circuit is subject to two counteracting effects. The number of parameters should be small for the device noise to be manageable, but also large enough for the circuit to be able to represent the solution. Dimensional expressivity analysis can optimize a candidate circuit considering both aspects. In this article, we will first discuss an inductive construction for such candidate circuits. Furthermore, it is sometimes necessary to choose a circuit with fewer parameters than necessary to represent all relevant states. To characterize such circuits, we estimate the best-approximation error using Voronoi diagrams. Moreover, we discuss a hybrid quantum-classical algorithm to estimate the worst-case best-approximation error, its complexity, and its scaling in state space dimensionality. This allows us to identify some obstacles for variational quantum simulations with local optimizers and underparametrized circuits, and we discuss possible remedies.
format Preprint
id arxiv_https___arxiv_org_abs_2107_07378
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Best-approximation error for parametric quantum circuits
Funcke, Lena
Hartung, Tobias
Jansen, Karl
Kühn, Stefan
Schneider, Manuel
Stornati, Paolo
Quantum Physics
High Energy Physics - Lattice
In Variational Quantum Simulations, the construction of a suitable parametric quantum circuit is subject to two counteracting effects. The number of parameters should be small for the device noise to be manageable, but also large enough for the circuit to be able to represent the solution. Dimensional expressivity analysis can optimize a candidate circuit considering both aspects. In this article, we will first discuss an inductive construction for such candidate circuits. Furthermore, it is sometimes necessary to choose a circuit with fewer parameters than necessary to represent all relevant states. To characterize such circuits, we estimate the best-approximation error using Voronoi diagrams. Moreover, we discuss a hybrid quantum-classical algorithm to estimate the worst-case best-approximation error, its complexity, and its scaling in state space dimensionality. This allows us to identify some obstacles for variational quantum simulations with local optimizers and underparametrized circuits, and we discuss possible remedies.
title Best-approximation error for parametric quantum circuits
topic Quantum Physics
High Energy Physics - Lattice
url https://arxiv.org/abs/2107.07378