On observability of N-level quantum systems
The purpose of this paper is to discuss necessary and sufficient conditions for observability of N-level quantum systems. We assume that the information about a physical system is given by the mean values \(Tr(\rho (t_ j)A_ i)=m_{A_ i}(t_ j)\), of n self-adjoint operators \(A_ 1,...,A_ n\) on \({\mathcal H}\) at some instants \(t_ 1<t_ 2<...<t_ s\). The question of the minimal number n of operators \(A_ 1,...,A_ n\) (physical quantities \({\mathcal A}_ 1,...,{\mathcal A}_ n)\) for which the quantum system \({\mathcal S}\) is \((A_ 1,...,A_ n)\)-observable is discussed.
observability of N-level quantum systems
scientific article; zbMATH DE number 3940014