Invisibility Cloaking Is Closer To Reality Than Science Fiction And Fantasy

H. G. Wells wasn’t the first to describe invisibility when he wrote and published “The Invisible Man” in 1897. Greek mythology featured the Cap of Invisibility that when worn made its bearer invisible. Perseus used it to slay the minotaur. Plato’s “Republic” described the Ring of Gyges whose wearer became invisible. The genie in Aladdin from the “Tales of The Thousand and One Nights” could make himself invisible. J. K. Rowling’s Harry Potter possessed an invisibility cloak. And Star Trek, the serial science fiction, featured the Romulan Empire whose ships used cloaking technology to make them invisible.

Fantasy and science fiction step aside, because physicists are bending light today to render objects invisible using negative refraction. If negative refraction sounds confusing, think about light refraction that isn’t negative. If you have ever looked at a straw in a glass of water, you witnessed positive refraction with the straw appearing to bend because as light passes from the air and through the water it is bent.

So what is happening with negative refraction? Instead of a visible bend, the light gets bent to cause the object you were viewing to vanish. That’s because negative refraction reverses light.

First described by Victor Veselago in a paper published in 1968, he used materials possessing negative refractive indices. This research stated that only artificially structured metamaterials could produce negative refraction and only on extremely small scales where a wavelength of light was longer than the nanomaterial being viewed.

Chiral metamaterials introduce the term chirality into the negative refraction explanation. Molecular chirality has been described as a significant characteristic of DNA and RNA, the building blocks of life on Earth. Chirality in the context of negative refraction, refers to chiral metamaterials that cross-couple electric and magnetic fields to cancel each out and thus render objects invisible.

Is negative refraction limited to metamaterials? The latest research appearing in Nature Communications on February 12, 2025, states that is not the case. The article, “Negative refraction of light in an atomic medium” describes arranging naturally occurring atoms in structured arrays that produce negative refraction. No metamaterials need to be involved.

The research into negative refraction using natural materials comes from Lancaster University in England, and the NTT Basic Research Laboratories in Japan. These researchers show that by using an optical lattice resembling an egg carton and constructed from standing light waves, atoms can be held in place and exhibit negative refraction characteristics.

Dr. Lewis Ruks from NTT Basic Research Laboratories describes the research results stating “These precisely arranged atomic crystals allow researchers to control the interactions between atoms and light with extraordinary precision, paving the way for novel technologies based on negative refraction.”

There are obvious stealth uses for negative refraction. But science fiction and television comedies can inspire other ways to use it such as:

• The cloaked observation post used in a Star Trek movie allowed Federation scientific teams to watch the development of a pre-industrial civilization without detection.
• The Cone of Silence was a privacy bubble featured in the Mel Brooks’ television comedy “Get Smart.” A equivalent could be created using negative refraction.

Cloaked invisibility could make it easier for observing animal behaviour in natural habitats. Negative refraction in construction materials could reduce noise for urban quiet zones.

Metamaterials and optical lattices are not the only technologies showing promise to make real objects disappear.

• Microwave frequencies are being used in military applications for radar avoidance.
• Using arrays of lenses to bend light has been shown to work in the visible spectrum with limitations.
• Thermal invisibility cloaks exist to hide electronic heat signatures.
• Electromagnetic wave-absorbing composite materials such as those used in the F35 jet have made it practically invisible to radar.
• Fractal colouration that mimics nature can hide a tank in plain sight on a battlefield.

So if you wish to hide in real life using a “Cloak of Invisibility,” move over Harry Potter, scientists appear to be developing several options for your consideration in the 21st century.