Radio frequency spectrum analyzer with a 5 THz bandwidth based on nonlinear optics in a CMOS compatible high-index doped silica waveguide

TL;DR

This paper introduces an all-optical RF spectrum analyzer with over 5 THz bandwidth, utilizing a CMOS-compatible high-index doped silica waveguide, enabling ultrafast RF spectrum measurements in the terahertz range.

Contribution

The work presents a novel high-bandwidth RF spectrum analyzer based on nonlinear optics in a CMOS-compatible waveguide, achieving over 5 THz bandwidth and demonstrating ultrafast RF measurement capabilities.

Findings

Achieved >5 THz RF spectrum analysis bandwidth.

Demonstrated measurement of femtosecond laser RF spectrum.

Optimized waveguide design for near zero dispersion in C-band.

Abstract

We report an all-optical radio-frequency (RF) spectrum analyzer with a bandwidth greater than 5 terahertz (THz), based on a 50-cm long spiral waveguide in a CMOS-compatible high-index doped silica platform. By carefully mapping out the dispersion profile of the waveguides for different thicknesses, we identify the optimal design to achieve near zero dispersion in the C-band. To demonstrate the capability of the RF spectrum analyzer, we measure the optical output of a femtosecond fiber laser with an ultrafast optical RF spectrum in the terahertz regime.