자료유형  

 학위논문

Control Number  

0017160693

International Standard Book Number  

9798382717098

Dewey Decimal Classification Number  

530.1

Main Entry-Personal Name  

Shlosberg, Ariel S.

Publication, Distribution, etc. (Imprint  

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

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

148 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.  

요약The objective behind developing quantum technologies is to perform computation and communication tasks that are infeasible using only classical resources. However, physical noise, due to interactions with the environment, and statistical noise, a result of the Born rule, are barriers to realizing the use cases of these technologies. In this thesis, we explore the effects of noise in a variety of quantum application settings and consider strategies to improve the performance of the protocols. A necessary step to executing useful tasks that require deep circuits is implementing error correction to handle faulty hardware. Motivated by a desire to inform near-term small circuit demonstrations of fault tolerance, we analyze the Bacon-Shor code and show that pseudo-thresholds are achievable on current hardware. Moreover, we demonstrate that a performance improvement can be realized by having error correction meta-parameters, such as the frequency of syndrome extraction, change as a function of the physical circuit structure and noise model. Next, we consider the effect of statistical noise on a key subroutine for variational quantum algorithms and design an adaptive algorithm for estimating quantum observables. This algorithm is shown to use information gained during the course of an experiment to outperform existing state-of-the-art methods, leading to an order of magnitude improvement in sample complexity, even for small problem instances. In the context of quantum networks, we study the effects of noise sources, such as photon loss, timing jitter, and dark counts, on dispersive-optics (DO) implementations of multi-party quantum key distribution (QKD). Using Gaussian quantum information extremality results, we provide achievable rate bounds for different noise models and a variety of network configurations (e.g. number of users in the network), helping inform the next generation of experiments and answering questions about how to scale these networks. Furthermore, we prove that the security analysis used in prior DO-QKD experiments is flawed in the finite-dispersion regime by providing a collective attack for the eavesdropper that has not been previously considered. We show that in realistic settings this results in a significant overestimation of the secure key rate.

Subject Added Entry-Topical Term  

Quantum physics.

Subject Added Entry-Topical Term  

Statistical physics.

Subject Added Entry-Topical Term  

Computer science.

Subject Added Entry-Topical Term  

Computational physics.

Index Term-Uncontrolled  

Physical noise

Index Term-Uncontrolled  

Statistical noise

Index Term-Uncontrolled  

Quantum key distribution

Index Term-Uncontrolled  

Dispersive-optics

Index Term-Uncontrolled  

Quantum algorithms

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:658082