Cavity-assisted magnetization switching in a quantum spin-phonon chain

We propose a mechanism for Néel switching via suppressed heating in a hybrid magnon-phonon cavity. A terahertz-driven cavity mode couples to a spin-phonon chain, and all particles dissipate energy through baths. Mean-field analysis shows that cavity photons enable switching by imbalancing the spin-density on sublattices—a symmetry-breaking effect absent without the cavity. Switching occurs at low fields (1−5V/μm) and selectively targets low magnon energies and perpendicular magnon modes. Laser fluence, damping, and photon loss tune the switching, advancing cavity-assisted optospintronics.