Tese de Doutorado #309: Juan Cano
Radiative Coupling between quantum dots in photonic crystal molecules
Autor: Juan Pablo Vasco Cano
Banca Avaliadora
Paulo Sérgio Soares Guimarães (orientador)
Física - UFMG
Pierre
Louis de Assis - Física - UFMG
Marcelo Paleólogo Elefteriadis de França Santos
IF/UFRJ
José Maria Villas
Bôas - IF/UFU
Danielle Sanvitto
NNL/Itália
Orientadores
Paulo Sérgio Soares Guimarães (orientador)
Departamento de Física - UFMG
Resumo do Trabalho
We theoretically address the possibility of using strongly coupled photonic crystal molecules to efficiently increase the mutual coupling rate between two quantum dots at large inter-dot distance. We treat the light-matter coupling with a semiclassical formalism based on Green’s tensors and the classical electromagnetic fields are solved within a guided-mode expansion approach. We find that when the quantum dots are in resonance with either of the two lowest energy modes of the photonic dimer, and in the strong cavity-cavity coupling regime, the inter-dot radiative coupling strength is proportional to the quality factors of the dimer modes being at least an order of magnitude larger than typical values achieved in one-dimensional systems. We also address the effects of structural disorder in the photonic crystal lattice on the mutual coupling between the two quantum dots, by assuming disorder parameters that are consistent with the current state-of-art fabrication technology. We find that the effective radiative coupling between the dots is robust against non-perfect quantum dot positioning and to structural disorder in the photonic crystal. Using a fully quantum mechanical model we quantify the entanglement between the quantum dots by the Peres-Horodecki negativity criterion. We show that it is possible to achieve negativity values of the order of 0.1 in the steady sate regime. We find that the entanglement is preserved as long as the dot-dot detuning is smaller than the exciton linewidth. We propose a device for practical applications in the transient dynamics.