There are many glorious science-based terms when it comes to surfing. We all talk about swells, of course, the underwater energy that creates a breaking wave. But we'll look at swell angles and ...

Figure 1: Schematics of the degenerate 4WM process on a thin nonlinear film. In this Letter, we experimentally demonstrate nonlinear optical negative refraction in thin metallic nanostructures. We use ...

Negative refraction of elastic waves has been studied and experimentally demonstrated in three- and two-dimensional phononic crystals, but Bragg scattering is impractical for low-frequency wave ...