This dissertation was carried out within the framework of the Quantum Information (QI). In particular, I have analyzed the main aspects: the protocol, the quantum states, the conditional measurements, and the decoherence. The ...

In the “standard” Gizburg-Landau approach, a phase transition is intimately connected to a local order parameter, that spontaneously breaks some symmetries. In addition to the “traditional” symmetry-breaking ordered phases, ...

The Dissertation Quantumness of Gaussian and non-Gaussian states in the op- tical domain collects my personal both theoretical and experimental contribu- tions, in the context of the Quantum Information theory in continuous ...

Nature always offers astonishing shows to the humankind. Gravitational lensing is one of the most intriguing effects which can be observed, and the astrophysical applications of such a phenomenon span from particle physics ...

In this thesis, we discuss several subjects connected with the framework of GR, in order to characterize astrophysical compact objects. The main purpose is to provide simple models describing gravitational fields generated ...

In questa tesi abbiamo studiato il trasporto di spin polarizzato e la torsione dello spin usando l’apporoccio della matrice di scattering secondo la teoria di Buttiker, nel caso di barriere magnetiche finite sotto l'effetto ...

The quanti cation of quantumness is necessary to assess how much a physical system departs from a classical behaviour and thus gauge the quantum enhancement in opera- tional tasks such as information processing and ...

After reviewing the formalism for describing flavor mixing, both in Quantum Mechanics and Quantum Field Theory, some consequences along three different directions are studied. First, it is proposed that flavor mixing can ...

In this thesis I will discuss the theory of two level systems and the theory of the oscillating particles in quantum eld theory. In the rst chapter I will consider the time evolution of a two level system, a qubit, to ...

Quantum systems can necessarily be viewed as open systems. As in classical physics, any realistic description of a system must take into account the cou- pling to an environment that strongly in uences the system itself. ...