A Polar Decomposition for Quantum Channels: Theory and Applications
| dc.contributor.author | Alexander, Matthew | |
| dc.date.accessioned | 2019-08-23T14:33:24Z | |
| dc.date.available | 2019-08-23T14:33:24Z | |
| dc.date.issued | 2019-08-23 | |
| dc.date.submitted | 2019-08-20 | |
| dc.description.abstract | Every potential benefit of quantum computers would be lost without methods to protect the computations from error. Quantum channels provide a framework for understanding error in quantum systems. In general, for a system of size d, a quantum channel may require as many as ~d^4 parameters to characterize it. We introduce the leading Kraus approximation, a simplification which reduces the number of parameters to ~d^2, while accurately approximating two figures of merit important to the experimentalist: the unitarity and average process fidelity. Additionally, applying the leading Kraus approximation declutters investigations into the set of quantum channels. When applied, a natural decomposition of channels arises, separating behaviour into coherent and decoherent contributions. We find that eliminating the coherent contribution provides the greatest increase to the fidelity, while decoherent processes provide a generalization of depolarizing channels. | en |
| dc.identifier.uri | http://hdl.handle.net/10012/14931 | |
| dc.language.iso | en | en |
| dc.pending | false | |
| dc.publisher | University of Waterloo | en |
| dc.subject | quantum theory | en |
| dc.subject | quantum computers | en |
| dc.title | A Polar Decomposition for Quantum Channels: Theory and Applications | en |
| dc.type | Master Thesis | en |
| uws-etd.degree | Master of Science | en |
| uws-etd.degree.department | Physics and Astronomy | en |
| uws-etd.degree.discipline | Physics (Quantum Information) | en |
| uws-etd.degree.grantor | University of Waterloo | en |
| uws.contributor.advisor | Emerson, Joseph | |
| uws.contributor.affiliation1 | Faculty of Science | en |
| uws.peerReviewStatus | Unreviewed | en |
| uws.published.city | Waterloo | en |
| uws.published.country | Canada | en |
| uws.published.province | Ontario | en |
| uws.scholarLevel | Graduate | en |
| uws.typeOfResource | Text | en |