Propagação de fótons em guias de onda acoplados

Abstract

In this work, the propagation of photons in coupled waveguide systems with different geometries and coupling parameters was studied. The theory of quantized electromagnetic light is capable of explaining various phenomena where the classical theory of Maxwell’s light fails. Initially, the field was quantized starting from the classical model, and the quantum states of light were defined, presenting some of their applications. Next, a brief description of waveguides was presented, explaining the phenomenon of coupling between neighboring waveguides, how to represent them in the context of field quantization, and providing a definition of fidelity and perfect state transfer (PST). With this in mind, it was possible to study the propagation of non-classical light in systems composed of these coupled waveguides, using a model with a linear geometry and non-constant coupling parameters, as well as two models with ring (or circular) geometry, each with two distinct coupling parameters: (a) constant and (b) non-constant. Fidelity was used as a parameter to identify perfect state transfer between different waveguides, where 2-photon and singlephoton Fock states and the 2 photon N 00N state were initially injected into the systems. It was observed that the value of fidelity is highly influenced by the geometry of the system, and perfect state transfer was observed in all models, for different numbers of waveguides.