Abstract
The general concept of Fano resonance is considered so as to show the possibility of this resonance in space. Using a recently found solution for a Bessel wave beam impinging on a dielectric sphere, we analyze the electromagnetic fields near a microsphere with different optical sizes and permittivity values. We theoretically reveal spatial Fano resonance when a resonant mode of the sphere interferes with an amount of non-resonant modes. This resonance results in a giant jump of the electric field behind the sphere impinged on by the first-order Bessel beam. The local minimum of the electromagnetic field turns out to be noticeably distanced from the rear edge of the microsphere. However, this is a near-field effect, and we prove it. We also show that this effect can be utilized for engineering a submicrometer optical trap with unusual and useful properties.
© 2021 Optical Society of America
Full Article | PDF ArticleMore Like This
Mikhail F. Limonov
Adv. Opt. Photon. 13(3) 703-771 (2021)
Fajun Xiao, Weiren Zhu, Malin Premaratne, and Jianlin Zhao
Opt. Express 22(2) 2132-2140 (2014)
Junxue Chen and Peixin Chu
J. Opt. Soc. Am. B 36(12) 3417-3427 (2019)