1301.0281 (T. Pramanik et al.)

Improving the fidelity of teleportation through noisy channels using
weak measurement    [PDF]

T. Pramanik, A. S. Majumdar

We investigate the problem of teleportation through two-qubit noisy channels with the aid of weak measurement to preserve the fidelity of teleportation. In particular, we consider a shared two qubit maximally entangled state as resource for teleportation, allowing one or both qubits to interact with the environment via the amplitude damping channel. We show that application of weak measurement and subsequent reverse measurement at suitable stages of the protocol lead to quantum fidelity for any value of the decoherence parameter when only one of the qubits interact with the environment. In the case when both qubits interact with the environment, the above-mentioned technique of weak measurement and its reversal enables one to achieve quantum fidelity for all magnitudes of decoherence for a sub-class of maximally entangled channels. The success probabilty of the protocol decreases with the strength of weak measurement, and is lower when both the qubits are affected by decoherence.

View original: http://arxiv.org/abs/1301.0281