Graphene analogue BCN: femtosecond nonlinear optical susceptibility and hot carrier dynamics

TL;DR

This paper investigates the third-order nonlinear optical properties and hot carrier dynamics of boron carbon nitride (BCN) and reduced graphene oxide (RGO), revealing distinct behaviors linked to their electronic structures.

Contribution

It provides the first detailed comparison of femtosecond nonlinear optical responses and carrier relaxation in BCN versus RGO, highlighting their different electronic band structures.

Findings

BCN exhibits optical limiting behavior, unlike RGO's saturable absorption.

Different relaxation times are observed in BCN and RGO, indicating varied carrier dynamics.

Distinct nonlinear susceptibilities are linked to their electronic band structures.

Abstract

Third-order nonlinear absorption and refraction coefficients of a few-layer boron carbon nitride (BCN) and reduced graphene oxide (RGO) suspensions have been measured at 3.2 eV in the femtosecond regime. Optical limiting behavior is exhibited by BCN as compared to saturable absorption in RGO. Nondegenerate time-resolved differential transmissions from BCN and RGO show different relaxation times. These differences in the optical nonlinearity and carrier dynamics are discussed in the light of semiconducting electronic band structure of BCN vis-\`a-vis the Dirac linear band structure of graphene.