Simulating Loading Dynamics of Laser-Cooled Atoms into Photonic Crystal Membrane – Capped Hollow-Core Fibers

A dielectric slab perforated with a lattice of wavelength-sized holes can be designed to act as a high-reflectivity mirror. A pair of such photonic crystal (PC) membranes can create a cavity when attached to either side of a piece of a hollow-core optical fiber. Laser-cooled atoms loaded into the few-micron diameter hollow core of the fiber through the PC membranes would form a new type of cavity-based quantum optics platform. Using numerical simulations, we estimate whether laser-cooled atoms can make their way through the holes of the PC membrane and be guided into the hollow fiber core with optical dipole trap. The atoms, released from a MOT (Magneto-Optical Trap) cloud placed vertically above the capped-fiber, will traverse through the scattered fields of the optical dipole trapping laser and also interact with the membrane when sufficiently close. These 3D potential maps are estimated by computational electromagnetics software. The trajectories of atoms are integrated with the help of parallel programs in order to estimate the overall loading efficiencies. We aim to explore different conditions of the system to assess loading feasibility: namely, the position, size and temperature of the MOT cloud, optical dipole trapping beam strength, and also, the geometry of the PC membrane.