Magnon Chaos in $PT$-Symmetric Cavity Magnomechanics

Here, we research a novel cavity magnomechanical system, where the magnon mode with Kerr nonlinearity driven by a microwave field couples to a phonon mode with a magneostrictive nonlinear interaction (radiation pressure-like). Based on these nonlinear properties, we numerically demonstrate magnon chaos in the PT-symmetry and PT-symmetry broken regimes in the system. In the PT-symmetry broken phase, the magnon-chaos driving threshold is lowered to a rather low levels benefited from the enhancement of the system nonlinearities. Moreover, by expenediently manipulating the phase transition between PT-symmetry and PT-symmetry broken regimes, we can switch the system between into and out of chaotic regimes. Our work may broaden the cavity magnomehcnaics and provide a promising application for magnetic chaos-related security communications.