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arXiv · quant-ph/9904036

Coherent States and the Reconstruction of Pure Spin States

Jean-Pierre Amiet·Stefan Weigert
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Abstract

Coherent states provide an appealing method to reconstruct efficiently a pure state of a quantum mechanical spin s. A Stern-Gerlach apparatus is used to measure (4s+1) expectations of projection operators on appropriate coherent states in the unknown state. These measurements are compatible with a finite number of states which can be distinguished, in the generic case, by measuring one more probability. In addition, the present technique shows that the zeroes of a Husimi distribution do have an operational meaning: they can be identified directly by measurements with a Stern-Gerlach apparatus. This result comes down to saying that it is possible to resolve experimentally structures in quantum phase-space which are smaller than hbar.

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Jean-Pierre Amiet, Stefan Weigert. 1999-04-08. Coherent States and the Reconstruction of Pure Spin States. https://arxiv.org/abs/quant-ph/9904036

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