Temperature Dependence of a Sub-wavelength Compact Graphene Plasmon-Slot Modulator

TL;DR

This paper explores how lowering temperature enhances the performance of a graphene-based plasmonic modulator, enabling ultra-compact, energy-efficient optical switching suitable for dense photonic circuits.

Contribution

It demonstrates a temperature-dependent design that achieves steep switching and ultra-short device lengths in graphene plasmonic modulators, advancing integrated photonics.

Findings

Cooling improves the extinction ratio and switching steepness.

Multi-layer graphene enables sub-micron device lengths.

The modulator approaches electronic scale lengths.

Abstract

We investigate a plasmonic electro-optic modulator with an extinction ratio exceeding 1 dB/um by engineering the optical mode to be in-plane with the graphene layer, and show how lowering the operating temperature enables steeper switching. We show how cooling Graphene enables steeping thus improving dynamic energy consumption. Further, we show that multi-layer Graphene integrated with a plasmonic slot waveguide allows for in-plane electric field components, and 3-dB device lengths as short as several hundred nanometers only. Compact modulators approaching electronic length-scales pave a way for ultra-dense photonic integrated circuits with smallest footprints