Magnon blockade in a strongly coupled nonlinear cavity–magnon system

The quantum blockade effect is one of the important control methods for various quantum states. Recently, magnon has gradually become the focus of quantum device research due to its excellent properties such as stability, high spin density, and tunability. This study investigates the generation of conventional and unconventional single and double magnon blockades, as well as magnon-induced tunneling effects, in strongly nonlinearly coupled cavity–magnon systems. By adjusting the coupling strength and the driving field, we achieved single and double magnon blockades, along with magnon-induced tunneling effects. Interestingly, we found that the transition from a magnon blockade to magnon-induced tunneling can be controlled by modulating the driving field. To validate the feasibility of our model, we examined the impact of thermal noise at an experimental temperature of 20 mK. Our proposed scheme may offer a method to manipulate few-magnon states and holds potential applications in quantum communication and quantum information processing.