Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: computing – Page 697

After developing a method to control exciton flows at room temperature, EPFL scientists have discovered new properties of these quasiparticles that can lead to more energy-efficient electronic devices.

They were the first to control flows at . And now, the team of scientists from EPFL’s Laboratory of Nanoscale Electronics and Structures (LANES) has taken their technology one step further. They have found a way to control some of the properties of excitons and change the polarization of the light they generate. This can lead to a new generation of electronic devices with transistors that undergo less energy loss and heat dissipation. The scientists’ discovery forms part of a new field of research called valleytronics and has just been published in Nature Photonics.

Excitons are created when an electron absorbs light and moves into a higher energy level, or “energy band” as they are called in solid quantum physics. This excited electron leaves behind an “electron hole” in its previous band. And because the electron has a and the hole a positive charge, the two are bound together by an electrostatic force called a Coulomb force. It’s this electron-electron hole pair that is referred to as an exciton.

Read more

Rice University physicists have created the world’s first laser-cooled neutral plasma, completing a 20-year quest that sets the stage for simulators that re-create exotic states of matter found inside Jupiter and white dwarf stars.

The findings are detailed this week in the journal Science and involve new techniques for cooling clouds of rapidly expanding to temperatures about 50 times colder than deep space.

“We don’t know the practical payoff yet, but every time physicists have laser cooled a new kind of thing, it has opened a whole world of possibilities,” said lead scientist Tom Killian, professor of physics and astronomy at Rice. “Nobody predicted that laser cooling atoms and ions would lead to the world’s most accurate clocks or breakthroughs in quantum computing. We do this because it’s a frontier.”

Read more

As if battered post-Christmas finances, a looming disorderly Brexit and the prospect of a fresh nuclear arms race were not enough to dampen spirits, astronomers have declared that a nearby galaxy will slam into the Milky Way and could knock our solar system far into the cosmic void.

The unfortunate discovery was made after scientists ran computer simulations on the movement of the Large Magellanic Cloud (LMC), one of the many satellite galaxies that orbits the Milky Way. Rather than circling at a safe distance, or breaking free of the Milky Way’s gravitational pull, the researchers found the LMC is destined to clatter into the galaxy we call home.

At the moment, the LMC is estimated to be about 163,000 light years from the Milky Way and speeding away at 250 miles per second. But simulations by astrophysicists at Durham University show that the LMC will eventually slow down and turn back towards us, ultimately smashing into the Milky Way in about 2.5 billion years’ time.

Read more

Mark Zuckerberg and his pediatrician wife Priscilla Chan have sold close to 30 million shares of Facebook to fund an ambitious biomedical research project, called the Chan Zuckerberg Initiative (CZI), with a goal of curing all disease within a generation. A less publicized component of that US$5 billion program includes work on brain-machine interfaces, devices that essentially translate thoughts into commands.

From a report: One recent project is a wireless brain implant that can record, stimulate and disrupt the movement of a monkey in real time. In a paper published in the highly cited scientific journal Nature on Monday, researchers detail a wireless brain device implanted in a primate that records, stimulates, and modifies its brain activity in real time, sensing a normal movement and stopping it immediately. Those researchers are part of the Chan Zuckerberg Biohub, a non-profit medical research group within the CZI. Scientists refer to the interference as “therapy” because it is designed to be used to treat diseases like epilepsy or Parkinson’s by stopping a seizure or other disruptive motion just as it starts.

“Our device is able to monitor the primate’s brain while it’s providing the therapy so you know exactly what’s happening,” Rikky Muller, a co-author of the new study, told Business Insider. A professor of computer science and engineering at the University of California, Berkeley, Muller is also a Biohub investigator. The applications of brain-machine interfaces are far-reaching: while some researchers focus on using them to help assist people with spinal cord injuries or other illnesses that affect movement, others aim to see them transform how everyone interacts with laptops and smartphones. Both a division at Facebook formerly called Building 8 as well as an Elon Musk-founded company called Neuralink have said they are working on the latter.

Read more

Researchers from MIT and elsewhere have recorded, for the first time, the “temporal coherence” of a graphene qubit—meaning how long it can maintain a special state that allows it to represent two logical states simultaneously. The demonstration, which used a new kind of graphene-based qubit, represents a critical step forward for practical quantum computing, the researchers say.

Superconducting quantum bits (simply, qubits) are artificial atoms that use various methods to produce bits of quantum information, the fundamental component of quantum computers. Similar to traditional binary circuits in computers, qubits can maintain one of two states corresponding to the classic binary bits, a 0 or 1. But these qubits can also be a superposition of both states simultaneously, which could allow quantum computers to solve complex problems that are practically impossible for traditional computers.

The amount of time that these qubits stay in this superposition state is referred to as their “coherence time.” The longer the coherence time, the greater the ability for the qubit to compute complex problems.

Read more

https://paper.li/e-1437691924#/

On the second balmy day of the year in New York, Neil Harbisson, a Catalan artist, musician, and self-professed “cyborg,” walked into a café in the Nolita district of Manhattan. The actor Gabriel Byrne was sitting at a table in the corner. Harbisson approached. “May I do a sound portrait of you? It will just take one minute. For nine years, I’ve been listening to colors,” he explained.

Byrne eyed his questioner from under raised eyebrows. On a slight frame, the 30-year-old Harbisson wore a white T-shirt, deep-pink jeans and black-and-white showman’s brogues. His face was angular, with an aquiline nose and a chin smudged with grown-out stubble. A small plastic oval floated in front of his forehead, attached to the end of a flexible stem that reached around from the back of his head and over a sandy pageboy mop, like the light on the head of an angler fish. This “eyeborg,” as Harbisson calls it, converts light into audible sound, with a pitch that varies according to the color of the light.

With a good-natured shrug, Byrne relented. Harbisson darted down next to his quarry, intent, but with a boyish smile that betrayed his excitement. He pointed the eyeborg first at Byrne’s ear, then his lips, then his left eye, then the bridge of his nose, and finally his salt-and-pepper hair, scribbling down musical notes on the back of a cardboard coffee-holder. Byrne gave him his agent’s email. When Harbisson got back to a computer, he would make a sound file that combined the notes from each bit of Byrne’s anatomy, and send it back to the actor. Harbisson’s collection already included Prince Charles, Nicole Kidman, and Al Gore.

Read more