High dimensional quantum information technology using photonics: protocol development and implementation schemes

includes bibliographical references and index

PhD; 2023; Electrical Communication Engineering

This thesis explores the realm of high-dimensional quantum information processing through the lens of photonics, focusing on developing and implementing quantum technologies based on d-level quantum systems known as qudits. Quantum information technology, with its transformative impact on information processing, has spurred innovations such as quantum computers, quantum cryptography, and quantum internet. However, the implementation challenges faced by current quantum information technology necessitate novel approaches, and photonics emerges as a promising solution. The research begins with a foundational analysis of sources and detectors for qudits, leveraging integrated photonic devices based on light propagation in optical waveguides. The modes of optical waveguides are proposed to represent qudits, and non-linear optical processes in micro-ring resonators are explored to develop single and multi-dimensional photon sources. A scheme for generating single photons using integrated optic ring resonators is presented. A cornerstone contribution lies in the development of a High-Dimensional version of the Quantum Key Distribution (QKD) Protocol BB84, introducing qudits into the realm of secure key distribution. The design and simulation of waveguide-based circuits for the practical implementation of both standard QKD and High-Dimensional QKD protocols support this conceptual advancement. The latter involves multi-mode waveguide-based circuits, enhancing the understanding of quantum communication in higher dimensions. A W-state encoding scheme for photonic qudits is proposed to address the critical aspect of error correction in quantum communication. This scheme holds promise as an error correction strategy for quantum memories and communication systems operating in higher dimensions. The thesis also extends its theoretical contributions into the experimental domain through collaborations with leading laboratories. The proposed experimental validation of the W-state protocol for qubits and qudits bridges the gap between theoretical frameworks and real-world applications. In summary, this thesis contributes significantly to the field of High-Dimensional quantum information processing using photonics. The integration of qudits into key quantum protocols, the design of practical waveguide-based circuits, and the development of novel error correction schemes lay the groundwork for the next frontier in quantum technology. The collaboration with esteemed laboratories further enriches the research, promising advancements that transcend theoretical boundaries and manifest in practical quantum communication systems.