Take some light bending metamaterials
, incorporate them into flexible fabric
and you have yourself an invisibility cloak. That's the theory anyway, and it doesn't stop at hiding objects. Building on the optical invisibility research
of Professor Sir John Pendry, researchers from Imperial College, London, have now proposed that similar metamaterials could be used to conceal entire events
– get ready for the "Spacetime cloak".
Scottish researchers are reporting a "practical breakthrough" that could lead to the development of that most sought after of wardrobe items – the invisibility cloak. The concept of the invisibility cloak (not pictured) is based around harnessing the unique electromagnetic wave-bending properties of metamaterials
, but this poses problems when it comes to creating flexible surfaces suitable for applications like clothing and contact superlenses
for visual prostheses... problems which the new material design known as "Metaflex" hopes to address.
They’re known as smart materials, memory materials or shape memory alloys, but it all boils down to the same thing: materials that hold one shape, but then take on another at a certain temperature. Such substances have been around for decades, but now researchers at Canada’s University of Waterloo have taken them to a new level. Using a patent-pending process, they can embed multiple shape memories in one object – in other words, while memory materials can presently take on only two shapes, going from one to the other at just one temperature, using the new process they could take on several shapes at several temperatures. The Multiple Memory Material Technology (MMMT) is said to work with virtually any memory material.
We’ve covered a few different research efforts looking to develop “invisibility cloak” technology on Gizmag, including 3D metamaterials that negatively refract visible and near-infrared light
and U-shaped “nano-rings”
that manipulate light. The latest news sure to get Harry Potter fans excited comes out of Michigan Technical University where Elena Semouchkina, an associate professor of electrical and computer engineering, has found ways to use magnetic resonance to capture rays of visible light and route them around objects, rendering them invisible to the human eye.
OK, first of all, what’s a light mill? It’s a simple rotary motor consisting of four flat vanes mounted to a central axis, which spins when subjected to light. Light mills have been around since 1873, mostly just as novelty items, and have pretty much always been at least a few inches tall. Less than a week ago, however, scientists at California’s Lawrence Berkeley National Laboratory announced the creation of a light mill just 100 nanometers in size. Unlike its bigger brothers, this tiny device might actually have some very practical applications.
Researchers at Southeast University in Nanjing, China have created a device that traps and absorbs electromagnetic waves coming from all directions, spiraling them inwards without any reflections, essentially creating an electromagnetic black hole. Qiang Cheng and Tie Jun Cui’s “omnidirectional electromagnetic absorber” draws in microwaves coming from any direction by spiraling radiation inwards, and converting its energy into heat. They plan on developing a device that can absorb visible light next.
are manmade substances designed to do some very weird things that natural materials don’t. The path of a beam of light through a natural
material like glass is predictable, but scientists from the California Institute of Technology (Caltech) have engineered an optical material that bends light in the wrong
direction. This new negative-index metamaterial (NIM) could have several valuable uses including invisibility cloaking
, superlensing (imaging nano-scale objects using visible light) and improved light collection in solar cells.
A Harry Potter-style invisibility cloak is one more step closer to reality thanks to the work of a research team at the FOM Institute for Atomic and Molecular Physics (AMOLF
) in the Netherlands, which has successfully harnessed the magnetic field of light to develop meta-materials that can deflect light in every possible direction.
Over the last few years we’ve covered the development of “invisibility cloaks” using metamaterials – man-made structured composite materials exhibiting optical properties not found in nature that can guide light to achieve cloaking and other optical effects. In 2006, scientists at Duke University demonstrated
in the laboratory that an object made of metamaterials can be partially invisible to particular wavelengths of light - not visible light, but rather microwaves. A few groups have even managed to achieve a microscopically-sized carpet-cloak
. Now researchers have developed software that can show what such a cloaked object will actually look like.
Harnessing the unique properties of metamaterials, researchers in China have recently published a work detailing the implementation of a thin air, broadband and remotely controllable 'invisible gateway' that is able to shield all types of electromagnetic waves while letting through all other physical objects.