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Simulating a single qubit channel using a mixed state environment

Geetu Narang·Arvind
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Abstract

We analyze the class of single qubit channels with the environment modeled by a one-qubit mixed state. The set of affine transformations for this class of channels is computed analytically, employing the canonical form for the two-qubit unitary operator. We demonstrate that, 3/8 of the generalized depolarizing channels can be simulated by the one-qubit mixed state environment by explicitly obtaining the shape of the volume occupied by this class of channels within the tetrahedron representing the generalized depolarizing channels. Further, as a special case, we show that the two-Pauli Channel cannot be simulated by a one-qubit mixed state environment.

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Geetu Narang, Arvind. 2006-11-06. Simulating a single qubit channel using a mixed state environment. https://doi.org/10.1103/physreva.75.032305

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