Quantum teleportation in terms of Dirac modes between accelerated observers

We have studied entanglement between two Dirac modes respectively observed by two independently accelerated observers. Due to Unruh effect, the entanglement degrades, but residual nonzero entanglement remains even when the accelerations of both observers are infinite. We have also investigated quantum teleportation using entangled Dirac modes, and calculated the fidelities in various cases. In general, the fidelity depends on the single-qubit state $\gamma|0\rangle +\delta|1\rangle$ to be teleported, as well as which Bell state to use. In the limit that both accelerations are infinite, the average fidelity in using $|\phi^\pm\rangle\equiv\frac{1}{2}(|00\rangle\pm |11\rangle)$ is $\frac{3}{4}$, while that in using $|\psi^\pm\rangle\equiv \frac{1}{2} (|01\rangle\pm |10\rangle)$ is $\frac{1}{2} + |\gamma|^2 |\delta|^2$.