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

Abstract

We show how the Aharonov-Bohm flux (AB) $ϕ_i$ and the dual gaps $(Δ_1, Δ_2)$ 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 $ϕ_i$. 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 $Δ_1$ resulted in higher values of $Q$. By increasing $ϕ_i$, 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.