High Q-factor (>10⁵) integrated resonators in the 7.5-9 µm wavelength range

Photonic integrated circuits in the mid-infrared wavelength range are undergoing rising development due to major applications in terms of sensing and environmental monitoring. In this context, we present the development of integrated resonators operating in the long wave infra-red spectral range, which are critical building blocks for many devices development. Challenges in terms of device design, fabrication and characterization in this spectral range will be discussed. As a main result, integrated resonators with Q factor higher than 10 ⁵ have been obtained using Ge-rich graded SiGe photonics circuits.