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arXiv · 1803.03471

Maximizing the encoded information via freezing the estimated parameters of a pulsed driven qubit

N. Metwally·S. S. Hassan
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Abstract

We use a rectangular pulse to freeze the possibility of estimating the coherent parameters ($\theta,\phi$) of a single qubit and the encoded information. It is shown that, as the possibility of estimating the parameters increases, the amount of encoded information decreases. The pulse strength and the detuning between the qubit and the pulse have a different effect on the estimation degree and the encoded information. We show that if the weight parameter, $\theta$ is estimated, the encoded information depends on the initial state settings. Meanwhile, the encoded information doesn't depend on the estimated phase parameter,$\phi$. These results may be useful in the context of quantum cryptography, teleportation and secure communication.

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N. Metwally, S. S. Hassan. 2018-03-09. Maximizing the encoded information via freezing the estimated parameters of a pulsed driven qubit. https://arxiv.org/abs/1803.03471

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