Graduate Program Events
Events on Friday, August 25th, 2023
- Final Thesis Defense
- Rydberg Physics in a Cryogenic System for Hybrid Quantum Interfaces
- Time: 10:00 am - 11:30 am
- Place: B343 Sterling
- Speaker: Juan Camilo Bohorquez, Department of Physics Graduate Student
- Abstract: Rydberg atoms coupled to microwave cavities are promising experimental platforms for the development of hybrid atom-superconducting quantum computing systems, and the quantum transduction of microwave quantum information into the telecom band. Experimental efforts to couple Rydberg atoms to two-dimensional microwave resonators face significant challenges due to electric field noise near the cavity surfaces, and the large dc polarizability of Rydberg states, which scales as $\ds \sim a_0^3 n^7$.
In this work we present experimental results in reducing the dc polarizability of Rydberg states by a factor of 7, using an off-resonant microwave dressing field. These experimental results are compared to a model for the dressed atom system. We also present analytical and numerical models for the excitation of Cesium atoms to Rydberg states via a quadrupole-dipole excitation scheme with reduced sensitivity to Doppler shifts, a significant source of noise in entangling gates requiring ground-Rydberg coherence for high fidelity operation. These models are used to engineer an experimental effort which demonstrates the first Rydberg Rabi oscillations using this scheme. Finally, we present a path forward for the Rydberg atom-microwave cavity coupling effort, using a bulk microwave cavity which requires atoms be placed further from surfaces, reducing the effects of dc electric field noise.