We propose an experimentally realizable nonreciprocal magnonic device at the single-magnon level by exploiting magnon blockade in a magnon-based hybrid system. The coherent qubit-magnon coupling, mediated by virtual photons in a microwave cavity, leads to the energy-level anharmonicity of the composite modes. In contrast, the corresponding dissipative counterpart, induced by traveling microwaves in a waveguide, yields inhomogeneous broadenings of the energy levels. As a result, the cooperative effects of these two kinds of interactions give rise to the emergence of the direction-dependent magnon blockade. We show that this can be demonstrated by studying the equal-time second-order correlation function of the magnon mode. Our study opens an avenue to engineer nonreciprocal magnonic devices in the quantum regime involving only a small number of magnons.
@article{arxiv.2112.02351,
title = {Dissipation-induced nonreciprocal magnon blockade in a magnon-based hybrid system},
author = {Yimin Wang and Wei Xiong and Zhiyong Xu and Guo-Qiang Zhang and J. Q. You},
journal= {arXiv preprint arXiv:2112.02351},
year = {2022}
}