Entanglement of Hybrid State in Noninertial Frame

We study quantum entanglement of hybrid state composed of coherent state and fermion in noninertial frame. Quantum entanglement increases from zero to the asymptotic value with the increase of the amplitude of the coherent state. The asymptotic value is equal to the value of quantum entanglement between two fermions in noninertial frame. This means that the larger amplitude is good for quantum entanglement against the Unruh effect. We find that the entanglement of the hybrid state cannot decrease to zero as the acceleration approaches infinity, while the bosonic entanglement vanishes completely in the infinite acceleration limit. Therefore, the residual entanglement of the hybrid state can be used to process relativistic quantum information tasks.