Minimal sets of dequantizers and quantizers for finite-dimensional quantum systems

The problem of finding and characterizing minimal sets of dequantizers and quantizers applied in the mapping of operators onto functions is considered, for finite-dimensional quantum systems. The general properties of such sets are determined. An explicit description of all the minimum self-dual sets of dequantizers and quantizers for a qubit system is derived. The connection between some known sets of dequantizers and quantizers and the derived formulae is presented.