Electromagnetically induced transparency under effects of light-mediated interactions, entanglement generation, and Fock states detection

Abstract

This thesis presents a brief compilation of the works developed during my doctorate, and can be divided basically into three main parts. In the first one, we show the changes caused by considering long-range interactions mediated by light in the phenomenon of electromagnetically induced transparency (EIT). We also show how these interactions can negatively impact population transfer through a stimulated Raman adiabatic passage (STIRAP) process, which may imply a technical limitation for EIT-based quantum memories, as the density and optical thickness of the samples have been increasing in recent experiments to obtain better efficiencies. In the second part, we propose two new schemes to generate highly entangled states in a system of two non-degenerate qubits coupled to a common bosonic mode, in both of which we use an EIT analogue to better understand and interpret the physics of the system. The first method relies on the injection of energy into the mode through a coherent pump to prevent the mode from decaying to vacuum, and under a certain parameter regime, we show that it is possible to obtain a maximally entangled steady state. In the second method, we transfer the population to the maximally entangled state through a STIRAP-like process. In the third and last part, we present a new idea for single-shot measurements of Fock states using the Autler-Townes effect, where two methods are proposed: both a destructive and a non-destructive one. The results presented were obtained from the experimental implementation of this scheme in a system of trapped ions, for measurements of phonon number states.