Optical fuse effect in a tunable liquid crystal waveguide with a Cr grating coupler

摘要

In this letter, we report on a spontaneous optical switch in a liquid crystal (LC) waveguide with a Cr grating coupler. We propose that this mechanism can be applied as a reusable optical fuse device. The dynamical response of the waveguide mode in the nematic liquid crystal was investigated in the near infrared. An incident continuous wave (cw) laser was used. When the incident intensity is below the threshold, the waveguide mode output intensity is proportional to the input. Above the threshold, the output quenches quickly. The sensitivity and the response speed can be controlled by adjusting the temperature with respect to the phase transition of LC.