Browse Physics

Specially designed waveguides act like conduits for high-frequency displacement currents.

The propagation of sound waves can be dramatically altered by forcing them to follow meandering channels, according to simulations.

Cloaking devices made of a composite of soft and hard materials can divert elastic vibrational waves around an object as though it wasn’t there.

Metamaterials can act as nonlinear mirrors, reflecting back an incoming electromagnetic wave at twice the frequency.

An acoustic diode made from linear metamaterials offers a more efficient way to control the propagation of sound than previous designs.

Researchers have designed the first emitter of circularly polarized light made from a stand-alone semiconductor device.

A cloak that can make an object undetectable by ultrasonic water waves has been successfully demonstrated.

Thanks to illusion optics, an open channel across a metamaterial slab is made invisible to light incident from the left.

A general approach works toward bringing the magical ideas of transformation optics closer to practical use.

Structurally engineered electromagnetic materials have now been made from active elements, expanding the range of possible optical effects in such so-called “metamaterials.”

Theorists propose that a nanostructured material could show what happens when the structure of spacetime changes, as some cosmologists have suggested may have occurred in the early universe.

The caveat that a carpet cloak must be made of an anisotropic material should not be ignored.

Scientists and novelists have been intrigued for centuries by the possibility of hiding an object so completely that neither trace of the object nor of its cloak is to be found. Recent theoretical developments show that cloaking is, in principle, possible for electromagnetic waves and to a limited extent for other types of wave, such as acoustic waves. An energetic program of experimental research has shown some of the schemes to be realizable in practice.

Čerenkov radiation with the emission cone reversed has been observed in a metamaterial with negative refractive index.

A proposed structure blocks sound waves in one direction but lets them pass in the other direction by first doubling their frequency.

Bent light can do more than render objects invisible—it can make them appear as something else.

Materials with unusual optical properties may allow the construction of sensors surrounded by a cloaking shell that makes the detectors undetectable.

A compact lens made from an acoustic metamaterial can focus ultrasonic waves to half a wavelength.

Researchers challenge the idea that special materials can bend light the ‘wrong’ way and create the perfect lens.