This false-color image of a blue lace agate mineral sample, taken on a multiphoton microscope, highlights how beautiful nonlinear optics can be. The red color is from second-harmonic generation in the quartz mixed into this sample. The green color is from third-harmonic generation, which highlights the banded regions that give agate its characteristic appearance. [Honorable Mention OPN 2020 Photo Contest]
—Benjamin M. Cromey, Ball Aerospace, Boulder, CO, USA
01 Dec 2020