Nonreciprocal unconventional magnon blockade via Barnett effect in a cavity magnonic system

This is the authors' abstract. We don't add key points for this paper.

We propose a scheme to achieve nonreciprocal unconventional magnon blockade via the Barnett effect in a cavity magnonic system. The system consists of a rotating yttrium-iron-garnet sphere and a microwave cavity that contains a Kerr nonlinear medium. A rotating magnetic object internally produces the Barnett effect, resulting in magnetization along the axis of rotation. By changing the direction of the magnetic field, the sign of the Barnett shift can be adjusted, thereby generating nonreciprocity. Under weak driving conditions, the optimal parameters for magnon antibunching are derived through analytical calculations, with the results showing high consistency with numerical simulations. Further research indicates that the Kerr nonlinear coefficient also exerts a certain influence on the generation of optimal magnon blockade. We have also analyzed the impact of non-ideal conditions on nonreciprocity. Therefore, the presented work provides a viable path toward generating nonreciprocal single-magnon devices and chiral magnon communications.