Formalismo das matrizes densidade na descrição de sistemas ópticos interagindo com dispositivos e o ambiente.

Abstract

In considering the polarization and coherence properties of light as the most investiga- ted, both for helping to understand many phenomena of interference and for having large technological applicability, it was recently proposed a theory based on density matrix alge- bra, which is able to describe such properties jointly. In a similar fashion, in this study we apply the coherence and polarization density matrix method to mathematically describe the effect of some optical devices and verify its applicability in experiments involving quantum erasers. Furthermore, by taking the temporal evolution of the reduced density matrix into account, we see that after interactions between the photons and environmental constituents, it is possible to verify the connection of the degree of entanglement between the system and the environment with the loss of quantum coherence by means of the von Neumann reduced entropy.