Controlling quantum entanglement via chiral Majorana interference

The control over quantum entanglement is fundamental to the advancement of large-scale quantum technologies. Here, we propose a chiral Majorana interferometer to govern the entanglement in a hybrid device consisting of a magnetic topological insulator and chiral topological superconductor. We show that quasiparticles outgoing from the domain wall of a chiral topological superconductor possess Nambu spinor entanglement because of the interference of chiral Majorana modes. It is found that the outgoing state can be manipulated continuously from the maximally entangled Bell state to the separable state by tailoring the type, thickness, and length of the domain wall. Based on the Clauser-Horne-Shimony-Holt inequality, it is shown that the concurrence quantifying the entanglement is directly given by the maximal Bell parameter measured from the current-current correlators.