Transmission of a dark hollow beam by anti-resonant hollow-core fiber

Transmission of dark hollow beams is crucial for blue-detuned guiding of cold atoms, and it is fundamental for cold-atom interferometers. We proposed four anti-resonant hollow-core fiber structures for transporting dark hollow beam, and then comparing their confinement loss. We chose the fiber structure with simpler structure and lower confinement loss to get fiber samples. Besides we built a fiber-coupled system to test the fiber properties. The experimental results show that the fiber can better maintain the light intensity of the hollow beam, which are crucial for guiding atoms.