Optical temperature sensor on the base of slot waveguide with LC filling

We consider design methods and principles of operation of an optical sensor for temperature measurement, which is based on ring microresonator made of slot and double-slot waveguides with LC filling. Guiding properties of a slot waveguide and, consequently, resonance condition of the microresonator depend on refractive index of the LC filling the slot. LC index changes with the temperature variation, thus resulting in variation of effective index of the slot waveguide. The measurement range and sensitivity of the sensor can be changed by modification of the waveguide and microresonator parameters, such as strip and slot width, ring radius, coupling coefficients, etc.