Geometric documentation and reconstruction of the church of the Monastery of San Prudencio (La Rioja, Spain)

[EN] Data contained in this record come from the following accademic activity (from which it is possible to locate additional records related with the Monastery):

Virtual Reconstruction of the Ancient State of a Ruined Church

Contributed to: 4th International Conference, EuroMed 2012, Limassol, Cyprus, October 29 – November 3, 2012.

Permutationally invariant state reconstruction

Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large-scale optimization problem, this is a major challenge in the design of scalable tomography schemes. Here we present an efficient state reconstruction scheme for permutationally invariant quantum state tomography. It works for all common state-of-the-art reconstruction principles, including, in particular, maximum likelihood and least squares methods, which are the preferred choices in today's experiments. This high efficiency is achieved by greatly reducing the dimensionality of the problem employing a particular representation of permutationally invariant states known from spin coupling combined with convex optimization, which has clear advantages regarding speed, control and accuracy in comparison to commonly employed numerical routines. First prototype implementations easily allow reconstruction of a state of 20 qubits in a few minutes on a standard computer