Alp Sipahigil (Advisor)

Color centers in silicon are a promising platform for realizing scalable quantum repeater nodes. The T center in silicon features long electron and nuclear spin coherence times and spin-dependent optical transitions. To build efficient spin-photon interfaces, we integrate T centers inside silicon photonic crystal cavities (PCC) which can achieve exceptional quality factors and small mode volumes, enhancing desired optical transitions. However, fabrication disorder limits the control precision of PCC resonances, requiring post-fabrication tuning strategies. We develop a novel approach...

Silicon, a mature platform for the semiconductor industry, has become a leading platform for future quantum technologies. As a high-purity material, it serves as a low-noise host for a variety of quantum defects. As a low-loss material, it is a desirable substrate and material platform for next generation quantum devices. However, the lack of piezoelectricity in silicon, due to its centro-symmetric structure, poses challenges for its electromechanical applications. For example, one common approach to realize electromechanics in silicon relies on hybrid integration with a different...

Superconducting quantum circuits are leading candidates for quantum computing. Scaling up these systems for practical applications will require compact coherent qubits that store the quantum states, high fidelity quantum gates that process them, and a scalable architecture that can accommodate complex error correction circuits. Meeting such requirements is mainly impeded by the unavoidable presence of two-level systems (TLS), which act as a decoherence source that results in the loss of quantum information via phonon emission. In this project, we engineer superconducting circuits...