High-Performance Photonic and Acoustic Interfaces for Qubits

Abstract

Solid-state-based quantum information technology has advanced significantly in recent years, with platforms such as diamond defect centers (e.g., silicon-vacancy and nitrogen-vacancy centers) playing a central role. Alongside the exploration of fundamental science, practical quantum applications demand scalable, efficient devices with ultra-low loss, high integrability, and robust fabrication processes. This thesis focuses on the fabrication and demonstration of novel devices, motivated by the need for better quantum interfaces. Key contributions include developing methods to confine and manipulate phonons in diamond, fabricating state-of-the-art photonic crystal cavities, demonstrating novel 2D diamond devices, and integrating diamond with other materials like lithium niobate for hybrid quantum systems. Additionally, the work on compact microcavities offers the potential for diverse applications, including quantum networking, lasers, and precision sensing. These innovations focus on different aspects of high-performance photonic and acoustic interfaces for qubits, pushing the boundaries of nanofabrication and quantum device performance and enabling scalable and practical solutions for emerging quantum technologies.