Gate-Tunable Optical Extinction of Graphene Nanoribbon Nanoclusters

TL;DR

This study demonstrates that the optical extinction of graphene nanoribbon nanoclusters can be tuned using a gate voltage, revealing strong nonlinear optical responses and extinction effects in the VIS-NIR spectrum.

Contribution

It introduces a method to control optical extinction in graphene nanoribbons via gating, using nanoscale junctions on LaAlO3/SrTiO3 interfaces.

Findings

Gate-tunable second and third harmonic responses in GNR nanoclusters.

Strong extinction of VIS-NIR light at specific wavelengths.

Observation of nonlinear optical effects in nanoscale GNR clusters.

Abstract

We investigate the optical response of graphene nanoribbons (GNRs) using the broadband nonlinear generation and detection capabilities of nanoscale junctions created at the LaAlO$_3$/SrTiO$_3$ interface. GNR nanoclusters measured to be as small as 1-2 GNRs in size are deposited on the LaAlO$_3$ surface with an atomic force microscope tip. Time-resolved nonlinear optical probes of GNR nanoclusters reveal a strong, gate-tunable second and third harmonic response, as well as strong extinction of visible to near-infrared (VIS-NIR) light at distinct wavelengths, similar to previous reports with graphene.