자료유형  

 학위논문

Control Number  

0017160711

International Standard Book Number  

9798382717173

Dewey Decimal Classification Number  

530.1

Main Entry-Personal Name  

Beckey, Jacob L.

Publication, Distribution, etc. (Imprint  

[S.l.] : University of Colorado at Boulder., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

198 p.

General Note  

Source: Dissertations Abstracts International, Volume: 85-11, Section: B.

General Note  

Advisor: Smith, Graeme.

Dissertation Note  

Thesis (Ph.D.)--University of Colorado at Boulder, 2024.

Summary, Etc.  

요약In this thesis, we develop theoretical tools aimed at facilitating the development of more useful quantum sensors and more efficient methods of multipartite entanglement quantification. In the first half, we study the quantum Fisher information (QFI) -- a canonical quantity in quantum metrology which captures the amount of information about unknown parameter(s) one can extract by measuring a quantum state that depends on those parameters. While the QFI can be computed easily in some simple cases, computing it for a generic quantum state whose dynamics might not be well-understood, is often intractable. We derive analytical, dynamics-agnostic bounds on the QFI that are computable on a quantum computer, allow one to estimate the QFI, and enable the variational preparation of the state that is approximately optimal for a given sensing task. We carefully prove their properties and point out relations to other quantities often used in quantum estimation theory.The second half of the thesis is dedicated to the study of a general family of multipartite entanglement measures, called the concentratable entanglements (CEs). We define the measures, show that many well-known measures are recovered as special cases, and then prove their essential mathematical properties. We then construct statistical estimators for these measures that utilize only one- and two-copy measurements, which are implementable using today's technologies. Moreover, we provide analytical performance guarantees in the form of upper bounds on the number of copies needed to estimate these measures to a desired precision, and provide upper bounds on the classical computation cost required to process the data from these protocols. Our work elucidates the various trade-offs for experimentalists striving to probe entanglement in quantum systems of many tens of qubits, and contributes to the quantum learning theory community aiming to quantify the hardness of estimating various properties of quantum states.

Subject Added Entry-Topical Term  

Quantum physics.

Subject Added Entry-Topical Term  

Theoretical physics.

Subject Added Entry-Topical Term  

Physics.

Index Term-Uncontrolled  

Quantum computing

Index Term-Uncontrolled  

Quantum entanglement

Index Term-Uncontrolled  

Quantum learning theory

Index Term-Uncontrolled  

Quantum metrology

Added Entry-Corporate Name  

University of Colorado at Boulder Physics

Host Item Entry  

Dissertations Abstracts International. 85-11B.

Electronic Location and Access  

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Control Number  

joongbu:658052