Magnetoelectronic and optical properties of nonuniform graphene nanoribbons

TL;DR

This paper explores the diverse electronic and optical behaviors of nonuniform bilayer graphene nanoribbons, revealing how magnetic quantization, confinement, and stacking influence their complex magneto-electronic spectra and optical responses.

Contribution

It introduces a classification of magneto-electronic spectra in nonuniform graphene nanoribbons based on numerical analysis, highlighting the impact of spatial wave function distributions.

Findings

Identification of four categories of magneto-electronic spectra

Discovery of diverse magneto-optical spectra linked to wave function distributions

Observation of prominent peaks in density of states with specific selection rules

Abstract

The electronic and optical properties of nonuniform bilayer graphene nanoribbons are worth investigating as they exhibit rich magnetic quantization. Based on our numerical results, their electronic and optical properties strongly depend on the competition between magnetic quantization, lateral confinement, and stacking configuration. The results of our calculations lead to four categories of magneto-electronic energy spectra, namely monolayer-like, bilayer-like, coexistent, and irregular quasi-Landau-level like. Various types of spectra described in this paper are mainly characterized by unusual spatial distributions of wave functions in the system under study. In our paper, we demonstrate that these unusual quantized modes lead to the appearance of such diverse magneto-optical spectra. Moreover, the investigation of the density of states in our model leads to the appearance of many prominent symmetric and weakly asymmetric peaks. The almost well-behaved quasi-Landau levels exhibit high-intensity peaks with specific selection rules, and the distorted energy subbands present numerous low-intensity peaks without any selection rules.