Producing Photonic Nanojet Outside of Immersed High Refractive Index Engineered dielectrics on Optical Fibers

In this work, we demonstrate the focusing of electromagnetic waves to produce a photonic nanojet (PNJ) at the output surface of an engineered high refractive index dielectric particle placed on top of an optical fiber and being surrounded by a cladding material. The generated focus (PNJ) is produced at a distance of
$\mathbf{0}.\mathbf{12}\boldsymbol{\lambda}_{\mathbf{0}}$
from the surface of the dielectric with a spatial resolution of
$\mathbf{0}.\mathbf{36}\boldsymbol{\lambda}_{\mathbf{0}}$
and
$\mathbf{0}.\mathbf{48}\boldsymbol{\lambda}_{\mathbf{0}}$
along the
$\boldsymbol{y}$
and
$\boldsymbol{x}$
axis, respectively. The proposed structure could have possible applications in sensing and imaging systems.