Photonic nanojet (PNJ), the sub wavelength confinement of light by dielectric microspheres is finding applications in nanoscale imaging, spectroscopy and nano lithography. These applications require control over the length and lateral dimension of the nanojets. In the paper we present the results of numerical simulation to show that a core shell microspheres can be used to generate photonic nanojet with controllable length and confinement by varying the relative refractive index of the microspheres and the separation between the core and shell centers. We show that a length of up to 27λ can be achieved when the core microsphere has lower refractive index than the shell and lateral dimensions down to λ/3 with core microsphere having higher refractive index.

Date Published: 15 June 2015
PDF: 6 pages
Proc. SPIE 9654, International Conference on Optics and Photonics 2015, 96541H (15 June 2015); doi: 10.1117/12.2182806

Published in SPIE Proceedings Vol. 9654:
International Conference on Optics and Photonics 2015
Kallol Bhattacharya, Editor(s)