Guess who's beyond these lovely bonnets péruviens pour bébé et enfant en coton ?
Metal subwavelength apertures have turned into essential devices to manipulate light at the nanoscale. However, experimentally characterizing the amplification brought by the nanoaperture on the excitation intensity remains a scientific and technical challenge. Such characterization is highly needed to fully understand and optimize the aperture’s design.
Our recent Optics Express manuscript describes a novel experimental method to directly characterize the aperture amplification on the excitation field independently on the emission process. We take advantage of the intrinsic nonlinear dependence of the fluorescence signal on the excitation intensity.
The most funny part is that we report enhanced nonlinear light-matter interaction using only a HeNe laser with less than 1mW CW power.
The Lycurgus cup is one the famous examples demonstrating the amazing optical properties of noble metal nanoparticles. Now with minimum chemistry knowledge, you can synthetize your own gold particles (or buy them directly on line) to realize your own Lycurgus cup.
Image at 90° illumination: the gold particles scatter light with orange color.
Image in transmission: the flask looks almost transparent with slight purple color.