60dB high-extinction auto-configured Mach--Zehnder interferometer

Understand

Imperfections in integrated photonics manufacturing have a detrimental effect on the maximal achievable visibility in interferometric architectures.

• These limits have profound implications for further photonics technological developments and in particular for quantum photonics technologies.
• Active optimisation approaches, together with reconfigurable photonics, have been proposed as a solution to overcome this.
• In this paper, we demonstrate an ultra-high (>60 dB) extinction ratio in a silicon photonic device consisting of cascaded Mach-Zehnder interferometers, in which additional interferometers function as variable beamsplitters.