Simulations of Rolled-up Optical Microcavities Using COMSOL Multiphysics® Software

Shilong Li [1],
[1] Shanghai Institute of Technical Physics (SITP), Shanghai, China
Published in 2016

By using a combination of top-down and bottom-up strategies (see Fig. 1), rolled-up optical microcavities have gained considerable attention owing to their excellent customizability [1]. For example, the resonant spectrum of a rolled-up optical microcavity is well defined by simply tailoring the rolling length before it rolls [2], as shown in Fig. 2. In order to have a good visualization for the electric field of resonant modes, a 3D rolled-up microcavity was simulated using the RF Module of COMSOL Multiphysics® software[3]. As seen in Fig. 3, the geometry of rolled-up structures is firstly simplified as a cylindrical ring with an inhomogeneous refractive-index distribution. Then, light is introduced through a near-field optical fiber with a Port Boundary Condition, and the far-field is terminated by a Perfect Matched Layer (PML). In the end, the electric field of a resonant mode in this simplified rolled-up optical microcavity is clearly visible. Moreover, we used COMSOL Multiphysics® software and the LiveLink™ for MATLAB® to create a precise rolled-up structure (see Fig. 4) so that the simulated electric field of resonant modes becomes more realistic.