Multifunctional Sensors and Switch in MDM Waveguide With Symmetric Dual Side-Coupled Nanodisks

A multirole waveguide with symmetric dual side-coupled nanodisk resonators, which can act as refractive index sensor, temperature sensor, and optical switch, is proposed and investigated numerically. By the finite-difference time-domain simulations, it is demonstrated that the value of the refractive index sensitivity of the nano-sensor can reach 1333 nm/RIU. And with ethanol fully filled in the resonators, it can act as a temperature sensor with temperature sensitivity of 0.52 nm/°C. Furthermore, by filling with liquid crystal material, the transmittance of the optical switch is up to 73.6% at the wavelength of 1310 nm. This letter may pave a way for multifunctional applications in the on-chip nano-sensing area.