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arXiv · 2002.12179

Zitterbewegung Effect in Graphene with Spacially Modulated Potential

Abdellatif Kamal·Ahmed Jellal
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Abstract

The Zitterbewegung (ZB) effect is investigated in graphene with spacially modulated potential near the original Dirac point (ODP) and extra Dirac points (EDPs). Our calculations show that to get the large ZB oscillations, the wave packet center must be at the angle $θ_0=0$ for EDPs located at zero-energy, or $θ_0=π/2$ for both ODP and EDPs at finite energy $\varepsilon=mπ$ ($m$ integer). By varying the parameters ($q_2, \mathbb{V}$) of the periodic potential and the initial momentum ($κ_0, θ_0$) of Gaussian wave packet, it is found that the frequency of the ZB oscillations is in the range $[10^{7}~\text{Hz}, 10^{13}~\text{Hz}$] depending on what type of EDP is generated and the amplitude reaches hundreds of angstroms but their attenuation becomes very slow. More analysis of the frequency shows the possibilities in experimentally realizing the ZB effect in our system.

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Abdellatif Kamal, Ahmed Jellal. 2020-02-27. Zitterbewegung Effect in Graphene with Spacially Modulated Potential. https://doi.org/10.1016/j.physe.2020.114193

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