Long-range coupling of silicon photonic waveguides using lateral leakage and adiabatic passage

TL;DR

This paper introduces a novel method for long-range coupling in silicon photonics that combines adiabatic passage with lateral leakage, enabling robust light transport between isolated waveguides via an optical bus.

Contribution

The paper presents a new approach combining adiabatic passage and lateral leakage for long-range coupling in silicon photonics, demonstrated through rigorous modeling.

Findings

Robust light transport between waveguides demonstrated.

Coupling bypassing intermediate waveguides shown.

Potential for new silicon photonic interconnects.

Abstract

We present a new approach to long range coupling based on a combination of adiabatic passage and lateral leakage in thin shallow ridge waveguides on a silicon photonic platform. The approach enables transport of light between two isolated waveguides through a mode of the silicon slab that acts as an optical bus. Due to the nature of the adiabatic protocol, the bus mode has minimal population and the transport is highly robust. We prove the concept and examine the robustness of this approach using rigorous modelling. We further demonstrate the utility of the approach by coupling power between two waveguides whilst bypassing an intermediate waveguide. This concept could form the basis of a new interconnect technology for silicon integrated photonic chips.