Magnon-squeezing as a niche of quantum magnonics

The spin excitations of ordered magnets - magnons - mediate transport in magnetic insulators. Their bosonic nature makes them qualitatively distinct from electrons. These features include quantum properties traditionally realized with photons. In this perspective, we present an intuitive discussion of one such phenomenon. Equilibrium magnon-squeezing manifests unique advantageous with magnons as compared to photons, including properties such as entanglement. Building upon the recent progress in the fields of spintronics and quantum optics, we outline challenges and opportunities in this emerging field of quantum magnonics.