Sensing an incoming signal is typically associated with absorbing a portion of its energy, inherently perturbing the measurement and creating reflections and shadows. Here, in contrast, we demonstrate ...

Typically, when a soundwave strikes a surface, it reflects back at the same fundamental frequency with a different amplitude. A new model shows that when a sound wave hits a nonlinear elastic ...

(Nanowerk News) An international team of researchers showed how a nonlinear elastic metasurface could convert a wave’s fundamental frequency to its second harmonic. Structural factors in metasurfaces, ...