Physicists and instrument makers in Leiden have succeeded in optimizing a spring that almost completely filters out ...

Unidirectional nonreciprocal transport is at the heart of many fundamental problems and applications in both science and technology. Here we study the novel design of wave diode devices by engineering ...

In this area we're focusing on the phenomena lurking between the domains of classical and quantum physics to expose the beautiful unifying mathematical ideas of asymptotics governing the behaviour of ...

Huygens' Principle (1678) implies that every point on a wave front serves as a source of secondary wavelets, and the new wave front is the tangential surface to all the secondary wavelets. But two ...