Femtosecond Laser Writing: Low Power Reconfigurability and Reduced Crosstalk in Integrated Photonic Circuits Fabricated by Femtosecond Laser Micromachining (Laser Photonics Rev. 14(10)/2020)

Femtosecond laser micromachining allows rapid and cost‐effective fabrication of thermally‐reconfigurable photonic integrated circuits with unique 3D geometries. In article number 2000024, Francesco Ceccarelli and co‐workers exploit thermally‐insulating 3D microstructures to decrease the power needed to induce a 2π phase shift down to 37 mW and to reduce the thermal crosstalk to a few percent for an inter‐waveguide separation down to 80 μm.