|Simulated near-field E 2 field enhancement distribution on xz plane with the amplitude mask apodization. Credit: Tomsk Polytechnic University|
Researchers from Tomsk Polytechnic University (Russia) and Bangor University (UK) have experimentally verified anomalous amplitude apodization for non-spherical particles for the first time. This phenomenon makes it possible to boost the magnifying power of microscopes and to record molecules and viruses more effectively. The study results were reported in Journal of Infrared, Millimeter, and Terahertz Waves.
"If we mask part of an ordinary lens surface with an optical filter, it will increase the magnifying power of the lens. But peak field intensity drops dramatically. The same effect is typical of spherical particle-lenses in nanoscopes or high-definition optical microscopes with a magnifying power of 50 nanometers. If we use non-spherical particles, including cylinders with illuminated butt-ends, as lenses, and if we mask part of the surface, it will simultaneously boost their magnifying power and peak field intensity. This is called the amplitude mask apodization effect," Professor Igor Minin from Tomsk Polytechnic University's faculty of electronic engineering noted.