Tunable integrated ring resonators by femtosecond laser micromachining
Abstract
Femtosecond Laser Micromachining (FLM) is a powerful technology for the fabrication of photonic devices. In this context, the integration of resonant elements within the platform represents a key advancement, enhancing both its versatility and its compatibility with a wide range of optical and fluidic components specifically enabled by this technique. Here, we report the realization of a tunable racetrack resonator fabricated by FLM and operating at telecom wavelengths. Leveraging low-loss waveguides, we obtained a Q factor of the resonator as high as 8 x 10^5 at critical coupling. Moreover, by integrating two thermo-optic phase shifters, we achieved both resonance tuning and dynamic control of the Q factor. This capability makes the device highly versatile for applications requiring dynamic spectral control, such as tunable filters, gyroscopes, and sensors.
Keywords
Cite
@article{arxiv.2511.16490,
title = {Tunable integrated ring resonators by femtosecond laser micromachining},
author = {Giulio Gualandi and Fabio Saretto and Daniele Pedroli and Giacomo Corrielli and Marco Liscidini and Roberto Osellame and Andrea Crespi},
journal= {arXiv preprint arXiv:2511.16490},
year = {2025}
}