Soliton-Assisted Massive Signal Broadcasting via Exceptional Points

TL;DR

This paper introduces a novel non-Hermitian optical system leveraging exceptional points to enable massive, high-throughput signal broadcasting in integrated photonics, surpassing traditional linewidth limitations by over three orders of magnitude.

Contribution

It demonstrates a new approach using parity-time symmetric coupled cavities to achieve over 100-channel signal broadcasting with Terabit-per-second rates, integrating soliton generation and broadcasting.

Findings

Achieved over 100 wavelength channels for signal broadcasting.

Surpassed microcavity linewidth constraints by over three orders of magnitude.

Enabled high-speed optical convolutional acceleration.

Abstract

Chip-scale all-optical signal broadcasting enables data replication from an optical signal to a large number of wavelength channels, playing a critical role in enabling massive-throughput optical communication and computing systems. The underlying process is four-wave mixing between an optical signal and a multi-wavelength pump source via optical Kerr nonlinearity. To enhance the generally weak nonlinearity, high-quality (Q) microcavities are commonly used to achieve practical efficiency. However, the ultra-narrow linewidths of high Q cavities prohibit achieving massive throughput broadcasting due to Fourier reciprocity. Here, we overcome this challenge by harnessing a parity-time symmetric coupled-cavity system that supports equally spaced exceptional points in the frequency domain. This design seamlessly integrates generation of dissipative Kerr soliton comb source and all-optical signal broadcasting into a unified nonlinear process. As a result, we realize soliton-assisted intracavity massive signal broadcasting with a channel count exceeding 100 over 200 nm wavelength range, resulting in Terabit-per-second aggregated rates. This throughput surpasses the intrinsic microcavity linewidth constraint (~200 MHz) by over three orders of magnitude. We further demonstrate the utility of this approach through an optical convolutional accelerator, highlighting its potential to enable transformative capabilities in photonic computing. Our work establishes a new paradigm for chip-scale photonic processing devices based on non-Hermitian optical design.