Stability of Self-Configuring Large Multiport Interferometers

Understand

Realistic multiport interferometers (beamsplitter meshes) are sensitive to component imperfections, and this sensitivity increases with size.

• Self-configuration techniques can be employed to correct these imperfections, but not all techniques are equal.
• This paper highlights the importance of algorithmic stability in self-configuration.
• Naive approaches based on sequentially setting matrix elements are unstable and perform poorly for large meshes, while techniques based on power ratios perform well in all cases, even in the presence of large errors.