Teleportation of quantum resources and quantum Fisher information under Unruh effect

Abstract

Considering a pair of Unruh–DeWitt detectors, when one of them is kept inertial and the other one is accelerated and coupled to a scalar field, we address the teleportation of a two-qubit entangled state $$ \left( |\psi _\mathrm{in}\rangle =\text {cos}~\theta /2 |10\rangle +e^{i\varphi }~\text {sin}~\theta /2 |01\rangle \right) $$ through the quantum channel created by the above system and investigate how thermal noise induced by Unruh effect affects the quantum resources and quantum Fisher information (QFI) teleportation. Our results showed while the teleported quantum resources and QFI with respect to phase parameter $$ \varphi $$ $$\left( F_{\text {out}}\left( \varphi \right) \right) $$ reduce with increasing acceleration and effective coupling, QFI with respect to weight parameter $$ \theta $$ $$\left( F_{\text {out}}\left( \theta \right) \right) $$ interestingly increases after a specified value of acceleration and effective coupling. We also find that the teleported quantum resources and the precision of estimating phase parameter $$ \varphi $$ can be improved by a more entangled input state and more entangled channel. Moreover, the precision of estimating weight parameter $$ \theta $$ increases for a maximally entangled input state only in large acceleration regime, while it does not change considerably for both maximally and partially entangled states of the channel. The influence of Unruh effect on fidelity of teleportation is also investigated. We showed that for small effective coupling the average fidelity is always larger than $$ \frac{2}{3} $$ .