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arXiv · 1512.05640

Heisenberg-Weyl Observables: Bloch vectors in phase space

Ali Asadian·Paul Erker·Marcus Huber·Claude Klöckl
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Abstract

We introduce a Hermitian generalization of Pauli matrices to higher dimensions which is based on Heisenberg-Weyl operators. The complete set of Heisenberg-Weyl observables allows us to identify a real-valued Bloch vector for an arbitrary density operator in discrete phase space, with a smooth transition to infinite dimensions. Furthermore, we derive bounds on the sum of expectation values of any set of anti-commuting observables. Such bounds can be used in entanglement detection and we show that Heisenberg-Weyl observables provide a first non-trivial example beyond the dichotomic case.

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Ali Asadian, Paul Erker, Marcus Huber, Claude Klöckl. 2015-12-17. Heisenberg-Weyl Observables: Bloch vectors in phase space. https://doi.org/10.1103/physreva.94.010301

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