Transport properties of a quantum dot based on the quantum anomalous Hall insulator

We study the transport properties of a quantum dot (QD) fabricated by a quantum anomalous Hall insulator. It is found that energy levels of the QD are quantized due to the quantum confinement effect, which leads to the appearance of the resonant-tunnelling phenomenon at low temperature. We also find that topological edge states form around the boundary of the QD, coexisting with the bulk states inside the QD. The electron transmission through the channels of the edge and bulk states drives the Fano interference, manifested as the asymmetric lineshape of the linear conductance spectrum. In addition, the spin polarization of this system is present. It shows that the spin-polarized current can be realized even in the absence of the external magnetic field, because of the breaking the time-reversal symmetry.