FINALIST: Microwave-shielded ultracold polar molecules

The manipulation of contact interaction via scattering Feshbach resonances has made ultracold atoms a highly tunable system for quantum simulation. In this talk, I will present the control of long-range interactions between ultracold polar molecules through microwave shielding and field-linked resonances, thereby enabling these molecules to serve as a novel platform for quantum simulation that extends beyond short-range interactions. Firstly, we utilize microwaves to create a repulsive barrier at an intermediate distance, stabilizing intermolecular collisions and allowing for evaporative cooling to achieve deep Fermi degeneracy. Secondly, by enhancing the long-range attractive interactions, we induce field-linked resonances that enhances the $p$-wave scattering amplitude. Finally, through a field-linked resonance, we associate pairs of diatomic molecules into tetratomic molecules. This series of work not only offers a novel approach for creating ultracold polyatomic molecules but also paves the way for exploring dipolar BCS-BEC crossover and topological $p$-wave superfluid.

*This work was performed at Max Planck Institute of Quantum Optics under the supervision of Dr. Xin-Yu Luo and Prof. Immanuel Bloch