ABSTRACT We propose a theoretical protocol for generating long‐distance Greenberger‐Horne‐Zeilinger states in a driven hybrid quantum system. The system consists of a central magnon coupled to multiple nitrogen–vacancy center spins positioned at a distance from the surface of the yttrium‐iron‐garnet sphere. A significant enhancement in the effective magnon‐spin coupling strength is achieved by driving the magnon with Kerr term. We analyze the dependence of the squeezing parameter on the driving field and adiabatically eliminate the magnonic mode under large detuning conditions via the Schrieffer–Wolff transformation, thereby establishing an effective all‐to‐all one‐axis‐twisting type spin–spin interaction essential for Greenberger–Horne–Zeilinger generation. Numerical simulations show that multi‐qubit Greenberger–Horne–Zeilinger states can be achieved even in the presence of dissipation. Furthermore, we investigate the impact of both inhomogeneous frequency broadening and non‐uniform coupling strengths between the magnon and spins. A cavity protection mechanism is introduced to mitigate frequency inhomogeneous broadening, while the tolerance to coupling inhomogeneity is also quantitatively evaluated.
Zeng et al. (Wed,) studied this question.