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Improving the fidelity of teleportation through noisy channels using weak measurement

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 نشر من قبل Tanumoy Pramanik
 تاريخ النشر 2013
  مجال البحث فيزياء
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We employ the technique of weak measurement in order to enable preservation of teleportation fidelity for two-qubit noisy channels. We consider one or both qubits of a maximally entangled state to undergo amplitude damping, and show that the application of weak measurement and a subsequent reverse operation could lead to a fidelity greater than $2/3$ for any value of the decoherence parameter. The success probability of the protocol decreases with the strength of weak measurement, and is lower when both the qubits are affected by decoherence. Finally, our protocol is shown to work for the Werner state too.



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