Side-chain electro-optic polymer modulator with wide thermal stability ranging from -46 °C to 95 °C for fiber-optic gyroscope applications

Electro-optic (EO) polymer modulators with a wide range of thermal stability from -46 °C to 95 °C for fiber-optic gyroscope applications are reported. The synthesized EO side-chain polymer used has a glass transient temperature (T_g) of 200 °C and a large EO coefficient of 25.2 pm/V in a real device measurement. Mach–Zehnder (MZ) intensity and optical phase modulators are implemented based on this high-T_g side-chain EO polymer, exhibiting ∼3.75 V half-wave voltage with 1.5 cm interaction length and 2.3 cm total length at 1.55 μm wavelength. The optical fiber-to-lens insertion loss is ∼7.5 dB in the MZ interferometers and ∼6 dB in the straight waveguides. We examine the long-term thermal stability of these devices and demonstrate their ability to meet the strict requirements of various EO device applications, particularly fiber-optic gyroscopes.