Ultracompact plasmonic racetrack resonators in metal-insulator-metal waveguides

TL;DR

This paper introduces ultracompact plasmonic racetrack resonators in metal-insulator-metal waveguides, addressing low extinction ratios in previous designs and significantly improving performance through analytical insights and novel structure.

Contribution

It provides a comprehensive analysis of MIM ring resonators' limitations and proposes a new racetrack resonator design with enhanced performance.

Findings

Analytical transmission relation for all-pass ring resonator with coupling loss

Identification of intrinsic reasons for low extinction ratios in MIM ring resonators

Demonstration of improved performance with plasmonic racetrack resonators

Abstract

Among various plasmonic waveguides, the metal-insulator-metal (MIM) type is the most promising for true subwavelength photonic integration. To date, many photonic devices based on MIM waveguides have been investigated, including resonators. However, most of the reported MIM ring resonators suffer from low extinction ratios. In this paper, we present a comprehensive analysis of the intrinsic reasons for the low performance of MIM ring resonators, and give the analytical transmission relation for a universal all-pass ring resonator which has coupling loss. Based on the analysis we propose the plasmonic racetrack resonators in MIM waveguides and show that the performance can be greatly improved.