High-intensity two-frequency photoassociation spectroscopy of a weakly bound molecular state

• Main Author: Kon, Wen Yu
• Other Authors: Kaden Hazzard
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Science::Physics::Optics and light
• Online Access: http://hdl.handle.net/10356/76878
• Institution: Nanyang Technological University

This project studies the two-frequency photoassociation process of molecules with a weakly bound halo state in a high-intensity regime. In the two-frequency photoassociation experiment of 86Sr performed by Aman et. al., where 86Sr atoms are coupled to the weakly bound halo state in the ground electronic channel, additional features are observed in the high-intensity regime. These features include higher order peaks and strong ac Stark shifts experienced by the spectral peaks. A simple three-level model with a two-frequency drive on each leg of the transition is introduced and is shown to capture the higher order peaks and their positions accurately. By using Floquet and perturbation theory, a simple formula is developed that replicates the binding energy of the halo state accurately. The threelevel model developed here will be a useful guide for future explorations in twofrequency photoassociation. In addition, a scheme using the weakly bound halo state and strong ac Stark shift observed in the 86Sr photoassociation experiment to tune the halo state into resonance is proposed. The proposed scheme is advantageous over typical optical Feshbach resonance in tuning scattering length due to its lower atom loss rate. This makes scattering length tuning using lasers more feasible.