  A protocol for realizing discrete-variable quantum teleportation in an
optomagnonic system is provided. Using optical pulses, an arbitrary photonic
qubit state encoded in orthogonal polarizations is transferred onto the joint
state of a pair of magnonic oscillators in two macroscopic yttrium-iron-garnet
(YIG) spheres that are placed in an optical interferometer. We further show
that optomagnonic entanglement swapping can be realized in an extended
dual-interferometer configuration with a joint Bell-state detection.
Consequently, magnon Bell states are prepared. We analyze the effect of the
residual thermal occupation of the magnon modes on the fidelity in both the
teleportation and entanglement swapping protocols.
