Spatial mode control and advanced methods for multi-platform quantum communication

Though state-of-the-art quantum computers are currently limited to only a handful of physical qubits, a quantum computer large enough to perform prime factorization of modern cryptographic keys, quantum simulation, and quantum-enhanced searching algorithms will likely become viable within a few decades. Such computers demand communication networks that preserve the qualities of the quantum states used as inputs and outputs; they also herald the end of the flavors of classical cryptography reliant on the complexity of factoring large numbers. As a result, future networks must include channels which preserve the states of single photons over useful distances (e.g., using quantum repeaters), and must deploy quantum-safe cryptography to ensure the safety of classical information passing over the network. Here we discuss strategies affecting several areas of a future quantum-enabled network: first, we demonstrate a technique for adaptively coupling single photons from point sources into single-mode optical fiber and apply the technique to coupling from quantum dots (a popular candidate for a future quantum repeater); secondly, we discuss various methods for simulating the effects of atmospheric turbulence on quantum cryptographic protocols in the laboratory, critical for understand the challenges facing free-space implementations of quantum communication. Thirdly, we demonstrate a technique that enables quantum cryptographic networks over free space channels to function in the presence of strong atmospheric turbulence using a multi-aperture receiver. Finally, we discuss our efforts to miniaturize a quantum key distribution system and operate a key distribution channel between flying multirotor drones.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2019

Author dc:creator

• Hill, Alexander D.

Contributors dc:contributor

• Kwiat, Paul G.
• Lorenz, Virginia O.
• Stack, John
• Peng, Jen-Chieh

• Quantum Communication, Quantum Optics, Adaptive Optics

Statement dc:rights

• Copyright 2018 Alexander Hill

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/102394

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/102394