Hydrogen Defects in Oxide Dielectrics: A Kinetic Perspective on Charge Noise in Si-Based Quantum Dot Architectures*

Silicon-based quantum dot architectures are leading candidates for scalable spin qubits, offering long coherence times and compatibility with existing semiconductor technology. However, gate fidelities remain limited by low-frequency (1/f) charge noise, the microscopic origin of which is still under debate. In this work, we focus on hydrogen-related defects in oxide dielectrics as a potential source of this noise. Due to their high mobility, these defects cannot be adequately described using the traditional configurational coordinate diagram. To address this, we develop a modified framework that incorporates kinetic effects essential for modeling the charge transition of highly mobile species. We also investigate quantum tunneling of hydrogen-related defects to identify possible candidates for the sources of the charge noise. Finally, we discuss how such defects can be characterized through electron paramagnetic resonance (EPR/ESR) and vibrational spectroscopies, such as infrared and Raman.