Symmetric Informationally Complete Quantum Measurements
نویسندگان
چکیده
We consider the existence in arbitrary finite dimensions d of a POVM comprised of d rank-one operators all of whose operator inner products are equal. Such a set is called a “symmetric, informationally complete” POVM (SIC-POVM) and is equivalent to a set of d equiangular lines in C . SIC-POVMs are relevant for quantum state tomography, quantum cryptography, and foundational issues in quantum mechanics. We construct SIC-POVMs in dimensions two, three, and four. We further conjecture that a particular kind of group-covariant SIC-POVM exists in arbitrary dimensions, providing numerical results up to dimension 45 to bolster this claim.
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