@article{9a61b5b73bf24fbd90b3dde811311460,
title = "Periodically focused modes in chains of dielectric spheres",
abstract = "We show that, theoretically, Brewster angle conditions for transverse magnetic polarized rays can be periodically reproduced in chains of spheres with index n = √3 giving rise to lossless periodically focused modes with 2D period, where D is the sphere diameter. Using ray tracing for a spherical emitter with the diameter D we show that chains of spheres work as filters of such modes at 1.72 < n < 1.85. This leads to tapering of the focused beams combined with the reduction of their attenuation along the chain. Experimentally, the beam tapering effect was observed in chains of 300 m sapphire spheres with index ∼1.77 in visible.",
author = "Arash Darafsheh and Astratov, {Vasily N.}",
note = "Funding Information: The authors thank A. Lupu, M. Tchernycheva, N. M. Fried, and M. A. Fiddy for stimulating discussions. The authors gratefully acknowledge support for our work from the National Eye Institute under Award Number R41EY019598. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Eye Institute or the National Institutes of Health. This work was also supported by the U.S. Army Research Office through Dr. J. T. Prater under Contract No. W911NF-09-1-0450 and by the National Science Foundation under grant ECCS-0824067.",
year = "2012",
month = feb,
day = "6",
doi = "10.1063/1.3684246",
language = "English",
volume = "100",
journal = "Applied Physics Letters",
issn = "0003-6951",
number = "6",
}