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arXiv · 1509.03144

Conditional cooling limit for a quantum channel going through an incoherent environment

Ivo Straka·Martina Miková·Michal Mičuda·Miloslav Dušek·Miroslav Ježek·Radim Filip
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Abstract

We propose and experimentally verify a cooling limit for a quantum channel going through an incoherent environment. The environment consists of a large number of independent non-interacting and non-interfering elementary quantum systems - qubits. The qubits travelling through the channel can only be randomly replaced by environmental qubits. We investigate a conditional cooling limit that exploits an additional probing output. The limit specifies when the single-qubit channel is quantum, i.e. it preserves entanglement. It is a fundamental condition for entanglement-based quantum technology.

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Ivo Straka, Martina Miková, Michal Mičuda, Miloslav Dušek, Miroslav Ježek, Radim Filip. 2015-11-24. Conditional cooling limit for a quantum channel going through an incoherent environment. https://doi.org/10.1038/srep16721

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