Modulatable optical radiators and metasurfaces based on quantum nanoantennas

Active Optical Metasurfaces Based on Defect-Engineered Phase-Transition Materials.

Active, widely tunable optical materials have enabled rapid advances in photonics and optoelectronics, especially in the emerging field of meta-devices. Here, we demonstrate that spatially selective defect engineering on the nanometer scale can transform phase-transition materials into optical metasurfaces. Using ion irradiation through nanometer-scale masks, we selectively defect-engineered th...

Optimal polarization conversion in coupled dimer plasmonic nanoantennas for metasurfaces.

We demonstrate that polarization conversion in coupled dimer antennas, used in phase discontinuity metasurfaces, can be tuned by careful design. By controlling the gap width, a strong variation of the coupling strength and polarization conversion is found between capacitively and conductively coupled antennas. A theoretical two-oscillator model is proposed, which shows a universal scaling of th...

Quantum plasmonic nanoantennas

We study plasmonic excitations in the limit of few electrons, in one-atom thick sodium chains, and characterize them based on collectivity. We also compare the excitations to classical localised plasmon modes and find for the longitudinal mode a quantum-classical transition around 10 atoms. The transverse mode appears at much higher energies than predicted classically for all chain lengths. The...

Perspective on molecular quantum plasmonic nanoantennas

Gain optimization of the optical waveguide based on the quantum box core/shell structure

In order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. To do this we have investigated optical waveguide both with and without optical pumping. The rate of absorption and emission using an array of AlGaAs/GaAs quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. By con...