@article{b583d8bf545f4ed2afe684eb2db721a5,
title = "Optical super-resolution by high-index liquid-immersed microspheres",
abstract = "It is experimentally shown that barium titanate glass microspheres with diameters (D) in the range 2-220 μm and with high refractive index (n ∼ 1.9-2.1) can be used for super-resolution imaging of liquid-immersed nanostructures. Using micron-scale microspheres, we demonstrate an ability to discern the shape of a pattern with a minimum feature size of ∼λ/7, where λ is the illumination wavelength. For spheres with D > 50 μm, the discernible feature sizes were found to increase to ∼λ/4. Detailed data on the resolution, magnification, and field-of-view are presented. This imaging technique can be used in biomedical microscopy, microfluidics, and nanophotonics applications.",
author = "Arash Darafsheh and Walsh, {Gary F.} and {Dal Negro}, Luca and Astratov, {Vasily N.}",
note = "Funding Information: The authors thank M. A. Fiddy, I. Vitebskiy, V. Kovanis, and D. M. Whittaker for stimulating discussions, A. D. Davies for sharing high NA microscope objective, and MO-SCI Corporation for donating some of the microspheres used in this work. This research was supported by the U.S. Army Research Office (ARO) through Dr. J. T. Prater under Contract No. W911NF-09-1-0450 and the National Science Foundation (NSF) under Grant No. ECCS-0824067. The fabrication work was supported by the U.S. Army Natick Soldier Center under Contract No. W911NF-07-D-001 and the SMART Scholarship Program, and has been approved for public release NSRDEC PAO#U12-307.",
year = "2012",
month = oct,
day = "1",
doi = "10.1063/1.4757600",
language = "English",
volume = "101",
journal = "Applied Physics Letters",
issn = "0003-6951",
number = "14",
}