Green Laser Casts Unexpected Shadow on Blue Light

In a surprising twist, scientists revealed that a high-power green laser can throw a 22% contrast shadow through a ruby crystal when intersecting with a blue laser. This phenomenon, dubbed 'optical nonlinear absorption,' challenges traditional light interaction theories by making the green beam behave like a shadow-casting object. The experiment used perpendicular laser setups, opening exciting avenues for advanced light control and optical switching technologies. Future research aims to explore diverse materials and wavelengths, potentially illuminating new tech frontiers.