Modular Linear Optical Circuits

TL;DR

This paper introduces a modular on-chip linear-optical circuit architecture that simplifies the construction and characterization of large interferometers, demonstrated through fabrication and testing of interconnected silica-on-silicon modules.

Contribution

The authors present a novel modular design for reconfigurable linear optical circuits, enabling scalable and easier-to-characterize large interferometers compared to traditional monolithic approaches.

Findings

Successfully fabricated and interconnected three silica-on-silicon modules.

Demonstrated a wide range of linear optical transformations.

Showed improved scalability and reconfigurability of optical circuits.

Abstract

We propose and demonstrate a modular architecture for reconfigurable on-chip linear-optical circuits. Each module contains 10 independent phase-controlled Mach-Zehnder interferometers; several such modules can be connected to each other to build large reconfigurable interferometers. With this architecture, large interferometers are easier to build and characterize than with traditional, bespoke, monolithic designs. We demonstrate our approach by fabricating three modules in the form of UV-written silica-on-silicon chips. We characterize these chips, connect them to each other, and implement a wide range of linear optical transformations. We envisage that this architecture will enable many future experiments in quantum optics.