Influence of Aharonov-Bohm flux and dual gaps on electron scattering in graphene quantum dots

TL;DR

This study investigates how Aharonov-Bohm flux and dual energy gaps influence electron scattering in graphene quantum dots, revealing oscillatory behaviors and parameter-dependent scattering efficiencies.

Contribution

It provides a detailed analysis of the effects of AB flux and dual gaps on scattering properties in GQDs, including new insights into oscillation suppression and parameter-dependent scattering regimes.

Findings

Scattering efficiency Q increases with dual gap Δ₁.

Q exhibits damped oscillations with AB flux φ_i.

Reflected current J_r^r shows periodic oscillations influenced by AB flux.

Abstract

We show how the Aharonov-Bohm flux (AB) $\phi_i$ and the dual gaps $(\Delta_1, \Delta_2)$ can affect the electron scattering in graphene quantum dots (GQDs) of radius $r_0$ in the presence of an electrostatic potential $V$. After obtaining the solutions of the energy spectrum, we explicitly determine the radial component of the reflected current $J_r^r$, the square modulus of the scattering coefficients $|c_m|^2$, and the scattering efficiency $Q$. Different scattering regimes are identified based on physical parameters such as incident energy $E$, $V$, $r_0$, dual gaps, and $\phi_i$. In particular, we show that lower values of $E$ are associated with larger amplitudes of $Q$. Furthermore, it is found that $Q$ exhibits a damped oscillatory behavior with increasing the AB flux. In addition, increasing the external gap $\Delta_1$ resulted in higher values of $Q$. By increasing $\phi_i$, we show that the oscillations in $|c_m|^2$ disappear for larger values of $r_0$ and are replaced by prominent peaks at certain values of $E$ and angular momentum $m$. Finally, we show that $J_{r}^r$ displays periodic oscillations of constant amplitude, which are affected by the AB flux.