Dispersion engineered high-Q silicon Nitride Ring-Resonators via Atomic Layer Deposition

TL;DR

This paper presents a method to engineer dispersion in silicon nitride ring resonators by applying hafnium dioxide coatings via atomic layer deposition, significantly enhancing their anomalous dispersion properties.

Contribution

The study introduces a novel dispersion engineering technique using ALD-coated hafnium dioxide to control and improve the dispersion characteristics of silicon nitride resonators.

Findings

Increased magnitude of anomalous dispersion

Broader bandwidth of dispersion enhancement

Results confirmed by frequency-comb-assisted spectroscopy

Abstract

We demonstrate dispersion engineering of integrated silicon nitride based ring resonators through conformal coating with hafnium dioxide deposited on top of the structures via atomic layer deposition (ALD). Both, magnitude and bandwidth of anomalous dispersion can be significantly increased. All results are confirmed by high resolution frequency-comb-assisted-diode-laser spectroscopy and are in very good agreement with the simulated modification of the mode spectrum.