Séminaire du LPTMS: Olivier Giraud

We introduce a new representation for density matrices of symmetric quantum states in finite-dimensional Hilbert spaces. This representation is particularly suited to the description of spin-j states in terms of linear combinations of spin coherent states. We describe several applications of such a representation: identification of the classical state closest to a given quantum state, construction of anticoherent spin states, classicality and separability criteria.