Fabrication of a multifunctional photonic integrated chip on lithium niobate on insulator using femtosecond laser-assisted chemomechanical polish

We report fabrication of a multifunctional photonic integrated chip on lithium niobate on insulator, which is achieved by femtosecond laser-assisted chemomechanical polish. We demonstrate a high-extinction-ratio beam splitter, a 1 × 6 optical switch, and a balanced 3 × 3 interferometer on the fabricated chip by reconfiguring the microelectrode array integrated with the multifunctional photonic circuit.