Elasto-Optic Phase Modulators in a Femtosecond-Laser Written Waveguide Platform

In the last decades, photonic integrated circuits have fostered tremendous advances in the development of new technologies. The adoption of a multitude of integrated waveguide components in a compact and monolithic platform indeed enables incomparable interferometric stability for processing classical and quantum optical signals on a large scale. This makes it possible to build high-quality optical devices for accomplishing diverse tasks in quantum simulations, quantum metrology, sensing and communications. In this context, the femtosecond laser micromachining (FLM) technology [1] has played an important role, as a non-lithographic waveguide fabrication method with unique capabilities in terms of three-dimensional design and rapid realization of the circuits.