Light emission, light detection and strain sensing with nanocrystalline graphene

TL;DR

This study investigates nanocrystalline graphene's potential for optoelectronic devices, demonstrating its use in light emission, detection, and strain sensing, comparable to crystalline graphene but with easier fabrication.

Contribution

It introduces nanocrystalline graphene as a versatile material for optoelectronic applications, including light emission, detection, and strain sensing, with scalable fabrication methods.

Findings

Nanocrystalline graphene can be used as an incandescent emitter.

It functions as a bolometric detector similar to crystalline graphene.

Exhibits piezoresistive behavior suitable for strain sensors.

Abstract

Graphene is of increasing interest for optoelectronic applications exploiting light detection, light emission and light modulation. Intrinsically light matter interaction in graphene is of a broadband type. However by integrating graphene into optical micro cavities also narrow band light emitters and detectors have been demonstrated. The devices benefit from the transparency, conductivity and processability of the atomically thin material. To this end we explore in this work the feasibility of replacing graphene by nanocrystalline graphene, a material which can be grown on dielectric surfaces without catalyst by graphitization of polymeric films. We have studied the formation of nanocrystalline graphene on various substrates and under different graphitization conditions. The samples were characterized by resistance, optical transmission, Raman, X-ray photoelectron spectroscopy, atomic force microscopy and electron microscopy measurements. The conducting and transparent wafer-scale material with nanometer grain size was also patterned and integrated into devices for studying light-matter interaction. The measurements show that nanocrystalline graphene can be exploited as an incandescent emitter and bolometric detector similar to crystalline graphene. Moreover the material exhibits piezoresistive behavior which makes nanocrystalline graphene interesting for transparent strain sensors.