Photonic hook generation under an electric dipole from a dielectric micro-cylinder.

• We firstly present two kinds of methods for the photonic hook generation by a dielectric micro-cylinder illuminated under an electric dipole using the finite element method. • A point dipole source, placed near the surface of the cylinder the propagation directions of the wave fronts illuminating the surface of the mesoscale dielectric cylinder are not parallel to each other, in contrast to classical plane-wave illumination. • Through changing the position and orientation of the point dipole, which can be considered as additional degrees of freedom to control the characteristics of the photonic hook, one can obtain the asymmetric illumination to produce the photonic hook. In this paper, we numerically investigate a photonic hook (PH) generated by a dielectric micro-cylinder illuminated under an electric dipole using the finite element method. At first, we show the properties of the photonic nanojet (PNJ) produced by the micro-cylinder under an electric dipole. Then, we find that a PH can be obtained when the electric dipole is moved at a certain distance along the direction perpendicular to the center line of the cylinder. Considering the rotation symmetry of the model, we firstly present that a PH can be generated by changing the orientation of the electric dipole. And the power flow of the PHs produced by different orientated dipoles are studied. Finally, the PHs properties affected by the gap distance between the micro-cylinder and the electric dipole and the refractive index of the micro-cylinder are investigated. Our results provide a method to generate a PH under a dipole illumination. And it may have potential applications in the quantum dot detection and microsphere super-resolution. [ABSTRACT FROM AUTHOR]