High-dimensional quantum communication over deployed fiber

Quantum key distribution (QKD) exploits the inherent strangeness of quantum mechanics to improve secure communication, enabling two pre-authenticated participants to establish symmetric encryption keys over long distances, without making any assumptions about the computational abilities of an adversary. QKD commonly relies on the transmission and detection of single photons to distribute the secret keys, but the secret-key generation rates are often limited by hardware, namely the ability to produce or detect nonclassical states of light. We address this challenge by using high-dimensional encoding to increase the secure information yield per detected photon. In this thesis, we present security analysis for and the first demonstrations of a resource-efficient high-dimensional QKD protocol, including two varieties of implementation that each have different strengths and weaknesses. We introduce a 42-km deployed fiber testbed that we use to demonstrate our high-dimensional QKD protocol. We also demonstrate the violation of a steering inequality, confirming that we can produce entanglement in the lab and distribute it over the deployed fiber. By these experiments, we demonstrate both the utility of our high-dimensional QKD protocol and the feasibility of our testbed for further applications in quantum communication and networking.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2018

Author dc:creator

• Lee, Catherine, Ph. D. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Dirk R. Englund.

• Electrical Engineering and Computer Science.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/115768

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/115768