Wave-packet dynamics in a graphene with periodic potentials

TL;DR

This study investigates how periodic potential barriers in graphene influence wave-packet propagation, revealing significant effects on transmission probabilities despite Klein tunneling, with implications for graphene nanodevice design.

Contribution

It introduces a detailed analysis of wave-packet dynamics in graphene with periodic potentials using the Dirac model and split-operator method, highlighting the impact of barrier parameters.

Findings

Transmission probability can decrease by over 20% due to lattice defects.

Barrier polarity affects wave packet transmission.

Wave-packet behavior is significantly altered by barrier size, height, and separation.

Abstract

We use the Dirac continuum model to study the propagation of electronic wave packets in graphene with periodically arranged circular potential steps. The time propagation of the wave packets are calculated using the split-operator method for different size, height and separation of the barriers. The time propagation of the wave packets is calculated using the split-operator method for various barrier sizes, heights, and separations. We found that, despite the pronounced Klein tunneling effect in graphene, the presence of a lattice of defects significantly impacts the propagation properties of the wave packets. For example, depending on the height and size of the incident wave packet, the transmission probability can decrease by more than 20\%. The alteration of the polarity of the potential barriers also contributes to the transmission probabilities of the wave packet in graphene. The obtained results could provide valuable insights into the fundamental understanding of charge carrier dynamics in graphene-based nanodevices.