Near Field - Quantum Dot Coupling in Plasmonic Nanoresonators

Metallic nanostructures (Plasmonics) have the ability to confine light close to their surfaces
far beyond the diffraction limit. It is therefore predicted that a quantum emitter at short
distance from a plasmonic resonator can be in strong coupling regime. Recent experimental
demonstrations however report an unpredicted high coupling strength between the emitter
and the plasmonic E/M field. In this thesis, we investigate the near-field influence of three
plasmonic nanoresonators on the strong coupling of semiconductor quantum dots from
two different approaches. First, after revisiting the theoretical results for models beyond
the dipole approximation, we perform Finite-Difference-Time-Domain (FDTD) analysis to
determine the field distribution in Plasmonic-QD systems. We then calculate the quadrupole
contribution to the coupling constant and report values as high as 24% Second, we investigate
the near-field strong coupling of the system by using the self-consistent Maxwell-Bloch
approach implemented in FDTD environment. After studying the coupling strength for
different sizes of the QD we predict ultra-fast Rabi oscillations between the emitter and
multiple plasmonic modes.

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