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arXiv · 0802.2822

A new approach to characterize qubit channels

Filippo Caruso·Vittorio Giovannetti
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Abstract

We analyze qubit channels by exploiting the possibility of representing two-level quantum systems in terms of characteristic functions. To do so, we use functions of non-commuting variables (Grassmann variables), defined in terms of generalized displacement operators, following an approach which resemble the one adopted for continuous-variable (Bosonic) systems. It allows us to introduce the notion of qubit Gaussian channels and to show that they share similar properties with the corresponding continuous-variable counterpart. Some examples of qubit channels are investigated using this approach.

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Filippo Caruso, Vittorio Giovannetti. 2008-02-20. A new approach to characterize qubit channels. https://doi.org/10.1142/s0219749908003864

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