IshaanBilala
Banned
Invisibility has long been employed in works of science fiction and fantasy, from “cloaking devices” on spaceships in the various Star Trek series to Harry Potter’s magic cloak. But physicists are beginning to think they can actually make devices with just these properties.
To achieve the feat of “cloaking” an object, they have developed what are known as “metamaterials”, some of which can bend electromagnetic radiation, such as light, around an object, giving the appearance that it isn’t there at all.
The first examples only worked with long-wavelength radiation such as microwaves.
One small device that made small objects invisible to near-infrared radiation and worked in three dimensions was unveiled by physicists from the UK and Germany earlier this year.
Its creators claimed there was nothing stopping them from scaling their invention up to hide larger objects from visible light – although others had pointed out a flaw in their design.
Now, researchers at Boston University and Tufts University claim that they have come up with an invisibility cloak that works within the terahertz band – the radiation between infrared and radio wavelengths – but could be modified to work with visible light. Intriguingly, it is made out of silk.
Light is electromagnetic radiation, made up of perpendicular vibrations of electric and magnetic fields. Natural materials usually only affect the electric component – this is what is behind the optics that we’re all familiar with such as ordinary refraction.
But metamaterials can affect the magnetic component too, expanding the range of interactions that are possible.
The metamaterials used in attempts to make invisibility cloaks are made up of a lattice with the spacing between elements less than the wavelength of the light we wish to ‘bend’.
To achieve the feat of “cloaking” an object, they have developed what are known as “metamaterials”, some of which can bend electromagnetic radiation, such as light, around an object, giving the appearance that it isn’t there at all.
The first examples only worked with long-wavelength radiation such as microwaves.
One small device that made small objects invisible to near-infrared radiation and worked in three dimensions was unveiled by physicists from the UK and Germany earlier this year.
Its creators claimed there was nothing stopping them from scaling their invention up to hide larger objects from visible light – although others had pointed out a flaw in their design.
Now, researchers at Boston University and Tufts University claim that they have come up with an invisibility cloak that works within the terahertz band – the radiation between infrared and radio wavelengths – but could be modified to work with visible light. Intriguingly, it is made out of silk.
Light is electromagnetic radiation, made up of perpendicular vibrations of electric and magnetic fields. Natural materials usually only affect the electric component – this is what is behind the optics that we’re all familiar with such as ordinary refraction.
But metamaterials can affect the magnetic component too, expanding the range of interactions that are possible.
The metamaterials used in attempts to make invisibility cloaks are made up of a lattice with the spacing between elements less than the wavelength of the light we wish to ‘bend’.