Asher Peres, Petra F. Scudo
Published 2000-10-25Version 1
We consider the use of N spin-1/2 particles for indicating a direction in space. If N>2, their optimal state is entangled. For large N, the mean square error decreases as N^{-2} (rather than N^{-1} for parallel spins).
Comments: 3 pages REVTEX and one PostScript figure
Journal: Phys. Rev. Lett. 86 (2001) 4160
Algorithmic construction of local models for entangled quantum states: optimization for two-qubit states
The quantum commuting model (Ia): The CHSH game and other examples: Uniqueness of optimal states
Determination of entangled quantum states of a trapped atom
