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arXiv:quant-ph/0310003 · Physical Review A

Quantum-state tomography for spin- l systems

Holger Friedrich Hofmann, Shigeki Takeuchi

Published Apr 23, 2004• 36 citations
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Abstract

We show that the density matrix of a spin-$l$ system can be described entirely in terms of the measurement statistics of projective spin measurements along a minimum of $4l+1$ different spin directions. It is thus possible to represent the complete quantum statistics of any $N$-level system within the spherically symmetric three-dimensional space defined by the spin vector. An explicit method for reconstructing the density matrix of a spin-1 system from the measurement statistics of five nonorthogonal spin directions is presented and the generalization to spin-$l$ systems is discussed.

DOI
10.1103/physreva.69.042108

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