Investigation of thermal effects on embedded microcoil resonators

In this paper we report on the theoretical and experimental analysis of such a sensor based on a microcoil resonator (MCR). A 2 μm-diameter silica microfiber (MF), fabricated using a ceramic microheater, was wrapped around a 1 mm-diameter glass rod to form a 3-turn MCR, and subsequently embedded in EFIRON UV-373 polymer. The Q-factor and free spectral range (FSR) were 5.3x104 and 486 pm respectively. The temperature-dependent transmission spectrum of the MCR was simulated by solving the coupled mode equations [3] whilst considering the thermal effects due to the thermo-optic effect (dn/dT) and thermal-expansion (dL/dT) of both materials. A sensitivity of 150 pm/οC (± 30%) and FSR of 0.5 nm were predicted.