By THOMAS STEVENSON.
If you were paying attention to the internets a few months ago, you may have seen this article. It’s about the research being done at the University of California, Berkeley, concerning something called an “ultrathin invisibility cloak.” Read that phrase again. “Ultrathin invisibility cloak.” Yep, there is a team working to make Harry Potter a reality.
The cloak in question is just 80 billionths of a metre thick. That’s about as thin as the skin of bacteria. It’s also made mostly of gold, which you might think would make it conspicuous. Gold is very bright and reflective, after all. But that’s actually the genius of the design. It reflects light in such a way that anything under the cloak, as well as the cloak itself, becomes invisible.
What we see (or don’t see) here is the latest in an exciting series of innovations in the field of nanotechnology. For many people, nanotech is one of those sciencey words that’s thrown around in newspapers but never really explained. It’s played upon a lot in sci-fi shows, where robots the size of viruses may be used for daring medical procedures.
Nanotechnology is defined as anything involving the manipulation of matter – atoms and molecules – at scales from 1 to 100 nanometres. What’s so special about this particular scale? First of all, as I said before, the membranes (skins) of bacteria and other cells fall within that size range. Tools used in nanotech research are able to fiddle with the structures of viruses, re-shape DNA and convince bacteria to produce fuel.
The idea that’s really driven nanotech forward is the concept of “tiny machines.” For decades, people have thought about how to make tools and machines smaller and smaller. In a famous talk (in the 1970s), Richard Feynman asked how small we could possibly make something. He discussed the challenges in building machines the size of molecules, then showed how living cells have already overcome some of those challenges. You can see a recording of this talk on YouTube if you’re interested.
Here’s why the scale from 1 to 100 nanometres is important. When we go down to that scale, we start to see some strange things. It’s at this miniscule size that the effects of quantum mechanics become significant. Quantum mechanics involves weird concepts like entanglement, which says that two particles can push or pull on each other, even across infinite distances, in a way that makes it look like they’re communicating. It’s so weird that even Einstein described it as “spooky.”
So people in nanotechnology get to experiment with funky quantum effects and build very small things. It’s a bit like putting together a jigsaw puzzle, only all the pieces keep changing shape, they are the size of atoms and nobody can imagine what the final picture looks like.
Despite the complexity, nanotech has already produced many amazing inventions. Describing them all here would take up way too much space, but luckily the National Nanotechnology Initiative has put together an impressive list. Have a look through it if you want all the details.
Here are some examples of applications that already affect your everyday life. Nano-scale particles of silver and other elements are used to combat harmful bacteria. That’s a common way to keep your food fresh and your socks not stinky. Also, extremely thin films on computer screens and sunglasses make them resistant to water or UV light. However, you should still not throw water at your computer, or look straight at the Sun.
And of course, as nanotech has evolved we’ve been able to make smaller and smaller electronic devices. The chips that make your computer, phone or iPod work are so common that it’s easy to overlook their extraordinary designs. But they’re the product of decades of painstaking, cutting-edge research. Modern music players are so thin and light because the chips inside them are getting smaller all the time.
We’re starting to see computer chips made at the nano-scale, even smaller than ever before. This type of electronics would allow us to build things like flexible phones or wearable screens. In the near future, your cell phone might be a paper-thin band you can wrap around your wrist!
There are also many ways that this technology could be used in medicine. Last year, a team at Stanford University designed a chip that can test a patient for Type-1 diabetes. Then there’s all the research into “nanobots,” tiny robots that could heal somebody from the inside.
Nanotechnology has a lot of promise and is already very helpful. It’s also safe and actually gives us a way to prevent bacterial infections. Just imagine what we could build next, as electronics get smaller and smaller. What do you think will be invented in, say, the next 50 years? Leave a comment below!