SNAP microresonators introduced by strong bending of optical fibers.

We introduce a new method of the fabrication of surface nanoscale axial photonic (SNAP) microresonators through strong bending of an optical fiber. We experimentally demonstrate that geometric deformation and refractive index variation induced by bending is sufficient for the formation of a SNAP bottle resonator with nanoscale effective radius variation (ERV) along the fiber axis. In our experiment, we bend the optical fiber into a loop and investigate the properties of the fabricated tunable bottle resonator as a function of the loop dimensions.