Phys.org January 31, 2023
When light scatters off a sphere, it produces a rich Mie spectrum full of overlapping resonances. Single resonances can be explained with a quantum analogy and result in Fano profiles. However, the full spectrum is so complex that recognizable patterns have not been found, and is only understood by comparing to numerical simulations. An international team of researchers (Sweden, Mexico) has shown the directional Mie spectrum of evaporating water droplets arranged in consecutive Fano Combs. They explained it by expanding the quantum analogy. This turns the droplet into an “optical atom” with angular momentum, tunneling, and excited states. This discovery can be applied to liquids other than water and may be useful when studying aerosol droplets in inhalers used for medication, for example. Small amounts of pollutants in the water change the way the droplets flash, which opens up the possibility of quick and easy measurements of chemical or biological pollutants in water droplets…read more. Open Access TECHNICAL ARTICLE
Counterpropagating trap used to record directional Mie spectra of evaporating water droplets. Credit: Phys. Rev. Lett. 130, 043804, 24 January 2023