Demonstration of a photonic-based linear temperature sensor

A photonic thermal sensor has been demonstrated using photonic waveguide-based Michelson interferometer (MI), with a footprint of only 120 μ m × 80 μ m. Operating at the wavelength ∼ 1550 nm, this ultracompact MI configuration obtains a nearly linear temperature response with a sensitivity of 113.7 pm/°C, which is ∼ 20 times higher than that of traditional fiber-optic thermal sensors. It is fabricated using standard CMOS processes. Benefitted from the advanced packaging technique, the proposed photonics sensor shows high thermal and mechanical stabilities, presenting a <0.1-dB power variation over the temperature range of 13 °C-95 °C, offering possibilities across a broad range of applications.