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arXiv · 2303.05291

Harnessing quantumness of states using discrete Wigner functions under (non)-Markovian quantum channels

Jai Lalita·K. G. Paulson·Subhashish Banerjee
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Abstract

The negativity of the discrete Wigner functions (DWFs) is a measure of non-classicality and is often used to quantify the degree of quantum coherence in a system. The study of Wigner negativity and its evolution under different quantum channels can provide insight into the stability and robustness of quantum states under their interaction with the environment, which is essential for developing practical quantum computing systems. We investigate the variation of DWF negativity of qubit, qutrit, and two-qubit systems under the action of (non)-Markovian random telegraph noise (RTN) and amplitude damping (AD) quantum channels. We construct different negative quantum states which can be used as a resource for quantum computation and quantum teleportation. The success of quantum computation and teleportation is estimated for these states under (non)-Markovian evolutions.

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Jai Lalita, K. G. Paulson, Subhashish Banerjee. 2023-07-04. Harnessing quantumness of states using discrete Wigner functions under (non)-Markovian quantum channels. https://doi.org/10.1002/andp.202300139

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