The geometry of single-qubit maps

Research output: Working paper

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The physically allowed quantum evolutions on a single qubit can be described in terms of their geometry. From a simple parameterisation of unital single-qubit channels, the canonical form of all such channels can be given. The related geometry can be used to understand how to approximate positive maps by completely-positive maps, such as in the case of optimal eavesdropping strategies. These quantum channels can be generated by the appropriate network or through dynamical means. The Str{\o}mer-Woronowisc result can also be understood in terms of this geometry.
Original languageUndefined/Unknown
Publication statusPublished - 6 Jun 2001


  • quant-ph
  • qubits
  • qubit maps

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