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Quantum-state tomography for spin-l systems

Holger F. Hofmann·Shigeki Takeuchi
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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 non-orthogonal spin directions is presented and the generalization to spin-l systems is discussed.

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Holger F. Hofmann, Shigeki Takeuchi. 2004-02-10. Quantum-state tomography for spin-l systems. https://doi.org/10.1103/physreva.69.042108

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