Abnormal high-$Q$ modes of coupled stadium-shaped microcavities
Abstract
It is well known that the strongly deformed microcavity with fully chaotic ray dynamics cannot support high-Q modes due to its fast chaotic diffusion to the critical line of refractive emission. Here, we investigate how the Q factor is modified when two chaotic cavities are coupled, and show that some modes, whose Q factor is about 10 times higher than that of the corresponding single cavity, can exist. These abnormal high-Q modes are the result of an optimal combination of coupling and cavity geometry. As an example, in the coupled stadium-shaped microcavities, the mode pattern extends over both cavities such that it follows a whispering-gallery-type mode at both ends, whereas a big coupling spot forms at the closest contact of the two microcavities. The pattern of such a 'rounded bow tie' mode allows the mode to have a high-Q factor. This mode pattern minimizes the leakage of light at both ends of the microcavities as the pattern at both ends is similar to whispering gallery mode.
Keywords
Cite
@article{arxiv.1408.4524,
title = {Abnormal high-$Q$ modes of coupled stadium-shaped microcavities},
author = {Jung-Wan Ryu and Soo-Young Lee and Inbo Kim and Muhan Choi and Martina Hentschel and Sang Wook Kim},
journal= {arXiv preprint arXiv:1408.4524},
year = {2015}
}
Comments
4 pages, 4 figures