Quantum Optics Seminar: Bálint Sárközi

Electromagnetically induced transparency with cold atoms in an optical resonator

Electromagnetically induced transparency (EIT) is a quantum interference effect that makes an otherwise opaque optically thick medium transparent over a narrow spectral range, caus ed by a sudden change in the refractive index. This leads to extremely low group velocities for light pulses, a phenomenon explored in “slow and stopped light” experiments now approaching applications in quantum information processing, like quantum memories and quantum repeaters. Our research focuses on the applications of EIT in quantum sensing, as this phenomenon is highly sensitive to small environmental changes, like in magnetic fields. My goal was to implement and investigate EIT in both a room temperature test setup and an ultra high vacuum environment with cold atoms in an optical cavity. As part of this, I tested and implemented a phase lock loop system for two independent lasers, a new technique in our group. Our long term goal is to use the developed EIT system to explore other two photon processes, such as grey molasses cooling, and to study room temperature EIT experiments using structured light with sensitivity enhanced by optical cavities.