Browsing Theses by Subject "quantum information"
Now showing items 41-60 of 87
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Liquid Crystal State NMR Quantum Computing - Characterization, Control and Certification
(University of Waterloo, 2013-08-30)Quantum computers offer the possibility of solving some problems more efficiently than their classical counterparts. The current forerunner in the experimental demonstration of quantum algorithms is Nuclear Magnetic Resonance ... -
Measurements of quantum fields and the Unruh effect: a particle detector perspective
(University of Waterloo, 2021-11-19)This thesis is devoted to the study of detector models in quantum field theory. A detector model aims to describe a hypothetical physical situation, realistic or not, in which a measurement is performed on a quantum field ... -
Measuring Trapped Ion Qudits
(University of Waterloo, 2019-09-26)Quantum information has typically focused on using 2-level qubits to perform simulation and computation. We propose to expand the number of levels for computation using qudits, where \(d>2\). Doing so could be a viable ... -
Microwave Quantum Optics using Giant Artificial Atoms and Parametrically Coupled Superconducting Cavities
(University of Waterloo, 2020-08-28)Artificially engineered atoms, built using superconducting electrical circuits, have had a broad impact on the field of quantum information and quantum computing. Based on the Josephson effect, superconducting qubits have ... -
Near-optimal quantum strategies for nonlocal games, approximate representations, and BCS algebras
(University of Waterloo, 2023-05-04)Quantum correlations can be viewed as particular abstract states on the tensor product of operator systems which model quantum measurement scenarios. In the paradigm of nonlocal games, this perspective illustrates a ... -
Non-local Quantum Systems with Infinite Entanglement
(University of Waterloo, 2022-08-18)The study of quantum entanglement under quantum information has mostly been done in the mathematical model of tensor product of Hilbert spaces. In infinite dimensions, this model cannot capture all cases of non-local ... -
Numerical Engineering of Adiabatic Quantum Operations
(University of Waterloo, 2020-01-23)Adiabatic quantum operations are ubiquitous in fields such as quantum information processing, quantum control, and magnetic resonance, where their high fidelity and general robustness renders them an essential tool for ... -
On the Hardness of the Quantum Separability Problem and the Global Power of Locally Invariant Unitary Operations
(University of Waterloo, 2008-09-18)Given a bipartite density matrix ρ of a quantum state, the Quantum Separability problem (QUSEP) asks — is ρ entangled, or separable? In this thesis, we first strengthen Gurvits’ 2003 NP-hardness result for QUSEP by showing ... -
Operational Approaches to Quantum Correlations and Particle Creation in Field Theory
(University of Waterloo, 2015-05-22)In this thesis we examine a variety of question regarding several quantum information-theoretic concepts as they manifest in the context of relativistic quantum fields. In particular, we study the qualitative and quantitative ... -
An Operational Road towards Understanding Causal Indefiniteness within Post-Quantum Theories
(University of Waterloo, 2022-01-07)A theory, whatever it does, must correlate data. We commit ourselves to operational methodology, as a means towards studying the space of Generalised Probability Theories that are compatible with Indefinite Causality. Such ... -
Parallel Repetition of Prover-Verifier Quantum Interactions
(University of Waterloo, 2012-01-05)In this thesis, we answer several questions about the behaviour of prover-verifier interactions under parallel repetition when quantum information is allowed, and the verifier acts independently in them. We first ... -
Parallelizing quantum circuit synthesis
(University of Waterloo, 2015-04-24)We present an algorithmic framework for parallel quantum circuit synthesis using meet-in-the-middle synthesis techniques. We also present two implementations thereof, using both threaded and hybrid parallelization ... -
The Practical Realization of Quantum Repeaters: An Exploration
(University of Waterloo, 2015-10-27)This thesis is an exploration of quantum repeaters from a practical point of view. Quantum repeaters are devices which help improve the quantum communication capacity of a lossy bosonic channel (which include photonic ... -
Quantum Algorithmic Techniques for Fault-Tolerant Quantum Computers
(University of Waterloo, 2019-10-01)Quantum computers have the potential to push the limits of computation in areas such as quantum chemistry, cryptography, optimization, and machine learning. Even though many quantum algorithms show asymptotic improvement ... -
Quantum Computation with Superconducting Parametric Cavity
(University of Waterloo, 2020-12-14)Multimode superconducting parametric cavity is a flexible platform that has been used to study a variety of topics in microwave quantum optics ranging from parametric amplification, entanglement generation to higher order ... -
Quantum experiments with single-photon spin-orbit lattice arrays
(University of Waterloo, 2019-09-19)The thesis introduces two single-photon experiments with the lattice of spin-orbit arrays. The basic background knowledge has been introduced in Chapter 1. Chapters 2-4 describe the detailed techniques used in these two ... -
Quantum Indefinite Spacetime: Part II
(University of Waterloo, 2018-09-10)We adopt an operational mode of thinking to study spacetime fluctuations and their impacts on questions of quantum gravity. Particular emphasis is put on studying causal structure fluctuations. The study is guided by the ... -
Quantum Information across Spacetime: From Gravitational Waves to Spinning Black Holes
(University of Waterloo, 2021-08-20)This thesis is split into two parts. In the first part, we investigate Bose-Einstein condensates (BECs) as a means to detect gravitational waves. For the detection of continuous gravitational waves, we study its sensitivity ... -
Quantum information in security protocols
(University of Waterloo, 2022-01-18)Information security deals with the protection of our digital infrastructure. Achieving meaningful real-world security requires powerful cryptographic models that can give strong security guarantees and it requires ... -
Quantum Information Processing with Adversarial Devices
(University of Waterloo, 2010-06-09)We consider several applications in black-box quantum computation in which untrusted physical quantum devices are connected together to produce an experiment. By examining the outcome statistics of such an experiment, and ...