Exciton transistors could create the energy-efficient electronics of the future

Last year, researchers at the École polytechnique fédérale de Lausanne (EPFL) in Switzerland developed a new type of transistor — one based on excitons, a special type of quasiparticle — which could be used in the future to make electronic devices smaller, faster, and more efficient. And now the same team has made another breakthrough by discovering new properties of excitons.

An exciton is a subatomic quasiparticle, meaning that it is not a particle in itself, but rather an interaction between two particles. In the case of excitons, they are made up of a bound pair of one electron and one electron hole. (An electron hole is a space in an atom where there is no electron but where one could exist.) The electron and electron hole become linked together when the electron absorbs a photon which gives it a higher level of energy, and the energetic electron moves position and leaves behind an electron hole. The electron is negatively charged and the hole that it leaves behind is positively charged, so the two bond in a process called the Coulomb attraction and form an exciton.

The EPFL team developed a transistor which used excitons instead of electrons. The advantage of this is that the exciton transistor can operate effectively at room temperature, while traditional electron transistors always produce heat when they operate. As transistors are a key component of circuits, having them produce no extra heat would potentially mean a big increase in energy efficiency and no need for large and bulky heat sinks or other cooling in electronic devices.

exciton transistor efficiency electronics 928x520 1
Visualization of exciton transistors which could be used to create more efficient electronics in the future LANES/EPFL

The latest breakthrough scientists have made is in controlling the properties of excitons. They have found a way to change the polarization of the light generated by the exciton by manipulating a property known as its “valley.” The valley is the maximum and minimum energies that a particle can express, and the valleys of electrons can be used to store information in a field known as “valleytronics” which could extend the ending of Moore’s Law. In the case of excitons, these valleys can be used to code and process information on a minuscule scale.

“Linking several devices that incorporate this technology would give us a new way to process data,” Andras Kis, head of EPFL’s Laboratory of Nanoscale Electronics and Structures, explained in a statement. “By changing the polarization of light in a given device, we can then select a specific valley in a second device that’s connected to it. That’s similar to switching from 0 to 1 or 1 to 0, which is the fundamental binary logic used in computing.”


Authentic, holistic, retro photography is in: Here are 2019’s predicted trends

What types of imagery are we most drawn to? According to recent stock photography data from Adobe, StoryBlocks, and Shutterstock, authentic, holistic, and humanitarian content will be in high demand in 2019.
Smart Home

DS3 Clean water-free swatches could be the future of cleaning products

DS3 Clean swatches were on display at CES 2019. The small swatches come in several types, including shampoo and toilet cleaner. They're great for travel, but their real impact is in how such supplies will be shipped and stored.

Keep your laptop battery in tip-top condition with these handy tips

Learn how to care for your laptop's battery, how it works, and what you can do to make sure yours last for years and retains its charge. Check out our handy guide for valuable tips, no matter what type of laptop you have.

Snooze soundly anywhere you lay your head with the best sleeping bags

A proper sleeping bag has the ability to make or break a camping or backpacking trip. Here are our picks for the best sleeping bags on the market to help you choose the correct bag for any type of outdoor adventure.
Emerging Tech

Fears about kids’ screen use may have been overblown, Oxford researchers find

Many people take it as gospel that digital technologies are harmful to young people’s mental health. But is this true? A recent study from the University of Oxford takes a closer look.
Emerging Tech

Meet Wiliot, a battery-less Bluetooth chip that pulls power from thin air

A tiny chip from a semiconductor company called Wiliot could harvest energy out of thin air, the company claims. No battery needed. The paper-thin device pulls power from ambient radio frequencies like Wi-Fi, Bluetooth, and cell signals.
Emerging Tech

Hexbot is a modular robot arm that does everything from drawing to playing chess

Who wouldn’t want their own personal robot arm to do everything from laser engraving to competing against you in a game of chess? That's what Hexbot, a new modular robot, promises to deliver.
Emerging Tech

The best drone photos from around the world will take your breath away

Most of today's drones come equipped with high-end cameras, which are quickly revolutionizing the world of aerial photography as we know it. Here are some of the best drone photos from around the world.
Emerging Tech

Too buzzed to drive? Don’t worry — this autonomous car-bar will drive to you

It might just be the best or worst idea that we've ever heard: A self-driving robot bartender you can summon with an app, which promises to mix you the perfect drink wherever you happen to be.
Emerging Tech

Scientists successfully grow human blood vessels in a Petri dish

Researchers have managed to grow human blood vessels in a Petri dish for the first time, and even to successfully implant them into live mice. The results could be a game-changer for diabetes.
Emerging Tech

Tiny animals discovered in Antarctic lake deep beneath the ice

Scientists have made a surprising discovery in Antarctica: the carcasses of tiny animals including crustaceans and a tardigrade were found in a lake that sits deep beneath over half a mile of Antarctic ice.
Emerging Tech

How long is a day on Saturn? Scientists finally have an answer

The length of Saturn's day has always been a challenge to calculate because of the planet's non-solid surface and magnetic field. But now scientists have tracked vibrations in the rings to pin down a final answer.
Emerging Tech

Awesome Tech You Can’t Buy Yet: camera with A.I. director, robot arm assistant

Check out our roundup of the best new crowdfunding projects and product announcements that hit the web this week. You may not be able to buy this stuff yet, but it sure is fun to gawk!
Emerging Tech

Google’s radar-sensing tech could make any object smart

Computer scientists have shown how Google’s Soli sensor can be used to make dumb objects smart. Here's why radar-powered computing could finally make the dream of smart homes a reality.