Design of optically actuated MEMS based optical switch using bragg grating

Abstract

Although optical communication networks are successful in providing reasonable amount of speed for communication, these networks are still facing an issue of electrical to optical and optical to electrical overhead while doing the optical switching task. Addressing this issue, we have proposed a new optically actuated MEMS based optical switch based on bragg gratings. The proposed device uses MEMS technology and hence is of very small dimension and it also uses new actuation mechanism which removes the electrical to optical and optical to electrical overhead and makes the optical networks all optical.

As a part of this work, I have analysed and simulated the reflection characteristics of fiber Bragg gratings in great detail. I have also calculated the temperature and pressure sensitivity of FBG in detail.

The proposed optical switch uses optical radiation pressure as an actuation mechanism. Photons possesses momentum, and hence, a beam of light can exert a force when reflected by a surface. Radiation pressure is nearly insignificant for most of the macro scale applications but it can be quite significant in microelectromechanical devices (MEMS).

After observing the magnitude of laser force I have proposed new MEMS structure which is a flat dielectric slab waveguide. Then I have derived the results for the change in reflected wavelength due to the change in Bragg grating’s characteristics which is embedded inside the microstructure. The change in Bragg grating will occur because of the deformation caused in the microstructure due to the application of optical radiation force.