High-Dimensional Quantum Information: From Sensing to Underwater Quantum Communication

Abstract

Quantum information has become an exciting field of research in the last 20 years, as experimental advancements allow us to control, manipulate, and detect states of quantum systems. A subset of this field studies the application of high-dimensional quantum states in communication, computing, and metrology. Specifically, this thesis explores the use of the high-dimensional Laguerre-Gaussian (LG) and vector vortex optical modes in underwater quantum communication channels. Making use of these high-dimensional states in quantum communication provides certain advantages including increased security and increased information capacity. We investigate underwater channels characterized by large optical turbulence and signal attenuation. These two challenges are of significant interest underwater communication channels. The detection of high-dimensional states also provides a great challenge for efficiently performing quantum information tasks as the dimensionality of the system increases. Here we study three different sensing sensing protocols, demonstrating how compressed sensing techniques can be very useful for high-dimensional quantum systems. In particular we perform high dimensional quantum process tomography, develop a compressed sensing protocol for LG modes which requires only intensity measurements, and a generalized adaptive compressed sensing protocol which can be used in any high-dimensional quantum systems.