Creation, applications and detection of entanglement in quantum optical systems

In this work, three applications aimed at studying or exploiting various aspects of entanglement are considered. In the first project, the entanglement between two atoms inside a multi mode resonator is investigated in the presence of retardation. Retardation is associated with the finite time required by a photon to propagate between atoms and cavity boundaries. It is found that retardation affects the atomic populations as well as the entanglement dynamics to a large degree. The second project is a study of entangled states of light to obtain an enhanced resolution. We have simulated optical centroid measurements for spatial resolution enhancement with various types of non-classical input states. By numerically simulating the measurement scheme, we optimize the detection parameters for an experimental implementation and also study the multi photon absorption required for quantum lithography. The third project uses the scattered light from a resonantly driven correlated system to obtain information about the system. Techniques have been proposed using which in certain detection directions, n-atom correlations can be directly accessed in an experiment via light scattering with a significant count rate. Moreover, such detection of correlations is not limited to a particular spatial geometry of atoms but can be utilized for generalized geometries, too