www.elsevier.com/locate/pla The quantum state tomography on an NMR system

The quantum state tomography on an NMR system is analyzed. The evolution of a given system by its Hamiltonian during the measurement can be understood as the inverse evolution of physical observables. In this way the NMR signal is expressed as a composition of the ensemble averages of observables, which facilitates the build-up of the procedure for estimating the density operator. The widely used procedure in which only single-qubit rotations are used to get information about the ensemble averages of a quorum of observables is devoted and the lower bound for the number of experiments is obtained