Microring Resonators Coupling Tunability by Heterogeneous 2D Material Integration

TL;DR

This paper demonstrates passive tunable coupling in silicon photonic micro-ring resonators by integrating few-layer MoTe2, enabling control over resonance properties and a method to determine the refractive index of TMD materials.

Contribution

It introduces a novel heterostructure of MoTe2 with micro-ring resonators for tunable coupling and presents a semi-empirical method to measure TMD refractive index near telecom wavelengths.

Findings

Achieved critical coupling with about 10% TMD coverage.

Demonstrated spectral resonance variation with TMD coverage.

Developed a method to determine TMD refractive index near telecom wavelengths.

Abstract

Atomically thin 2D materials provide a wide range of basic building blocks with unique properties, making them ideal for heterogeneous integration with a mature chip platform. An understanding the role of excitons in transition metal dichalcogenides in Silicon photonic platform is a prerequisite for advances in optical communication technology, signal processing, and possibly computing. Here we demonstrate passive tunable coupling by integrating few layers of MoTe2 on a micro-ring resonator. We find a TMD-to-rings circumference coverage length ratio to place the ring into critical coupling to be about 10% as determined from the variation of spectral resonance visibility and loss as a function of TMD coverage. Using this TMD ring heterostructure, we further demonstrate a semi-empirical method to determine the index of an unknown TMD material (nMoTe2 of 4.36+.011i) near for telecommunication-relevant wavelength.