Shaffer, 350 Water St. Cambridge, Massachusetts 2,141, Phone: 617.947.2365; Email: Donald. Or to: John R. Teijaro, 10,550 North Torrey Pines Rd. La Jolla, California 92,037, USA. Phone: 858.784.7397; Email: [email protected].
Category: mobile phones
Dog-bone design helps 2D nanoribbon transistors stay fast and efficient as widths shrink
Transistors, small semiconductor-based switches that control the flow of electricity, are central components of all electronic devices, from computers to smartphones, wearables, sensors and smart appliances. Over the past decades, electronics engineers have been continuously working to boost the speed and performance of transistors while also reducing their size.
A promising approach for miniaturizing transistors entails the use of two-dimensional (2D) semiconductors, materials that are only one or a few atoms thick. Despite their potential, most high-performing 2D transistors have so far been demonstrated using relatively wide channels, and it has remained unclear whether their performance can be preserved when the channels are made much narrower.
Researchers at Stanford University recently developed new compact transistors based on narrow strips of monolayer 2D semiconducting materials known as nanoribbons. These transistors, introduced in a paper published in Nature Nanotechnology, were found to perform remarkably well despite their small size, outperforming previously developed nanoribbon transistors based on the same 2D materials.
Scientists catch classical space-time crystals moving like Majorana quasiparticles
A research team from Hiroshima University, the University of Colorado, and other collaborators have demonstrated that space-time crystals—exotic structures that, under external drive, loop endlessly through both space and time—can be created using everyday liquid-crystal materials.
For the past decade, physicists have been fascinated by time crystals. Unlike normal crystals (such as salt or diamonds), which have repeating molecular patterns in space, time crystals have patterns that repeat at regular intervals in time. Previously, scientists believed these bizarre structures could exist only in highly complex, fragile quantum systems at near-absolute-zero temperatures, such as trapped ions or quantum simulators. However, in a collaborative study published in Nature Communications, researchers successfully created them in a classical, room-temperature liquid-crystal system.
To achieve this, the team took a liquid-crystal material—similar to the fluid used in smartphones and television screens—and doped it with ionic substances. They then applied a rhythmic, repeating electrical signal to the fluid. Using advanced computer models and optical microscopes, the researchers observed a surprising phenomenon known as period-doubling. Even though the electrical drive pumped energy into the fluid at a set internal rhythm, the liquid crystals spontaneously locked into a pattern that repeated only every two cycles of the electricity.
Abstract: Address correspondence to: Adam D
Bachstetter, Spinal Cord and Brain Injury Research Center, Department of Neuroscience, University of Kentucky, 741 S. Limestone Street, BBSRB Room B459, Lexington, Kentucky 40536–0509, USA. Phone: 859.218.4315; Email: [email protected].
Abstract: Address correspondence to: Douglas E
Vaughan, Northwestern University Feinberg School of Medicine, Simpson Querrey Biomedical Research Center 8–516303 E. Superior St., Chicago, Illinois 60,611, USA. Phone: 312.503.1531; Email: [email protected].
Electric ‘nose’ can smell when your food’s gone bad
Most of us have used the sniff test to decide whether a slightly expired bottle of milk or a week-old box of takeout is still good to eat. But while the human nose can be quite astute, it doesn’t always catch everything. Each year, millions of people in the U.S. are sickened by food-borne pathogens that thrive in undercooked or spoiled food.
Luckily for our collective stomachs, a new “electronic nose” developed at UC Berkeley can detect the scents associated with spoiled food much more accurately than the human nose. It can also sniff out the presence of common food allergens, like walnuts and peanuts, which can be deadly for those with sensitivities. The nose is described in a new study published in the journal Science Advances.
“I think ‘smart’ fridges—which come with sensors that you can control on your phone—would be a great application for this kind of technology,” said study lead author Carla Bassil, a Ph.D. student in electrical engineering and computer sciences at Berkeley and a member of the Javey Research Group. “How great would it be if your fridge could tell you, ‘Hey, your broccoli’s going to go bad soon, so you should probably eat that,’ Or, ” Your chicken is on its last day’?”
New Rokarolla Android malware targets 217 banking, crypto apps
A new Android banking trojan named Rokarolla is targeting 217 banking and cryptocurrency applications using an extensive set of 137 commands.
The malware is distributed via malicious websites purporting to provide the Google Chrome or TikTok app, and can take complete administrative control of a compromised device.
Its capabilities include stealing lock screen credentials, contact lists, and SMS data, as well as using keyloggers to continuously record user input.
Organic molecule with ultranarrow emission spectrum could lead to better LEDs
Over the past several decades, light sources have gradually transitioned to light-emitting diodes, or LEDs, and inorganic LEDs are now used across a wide range of applications. In parallel, organic LEDs, or OLEDs, have become widely used in display technologies.
OLEDs in particular offer significant advantages in devices such as smartphones, including higher resolution and lower power consumption. All LEDs operate based on spontaneous emission, which is inherently broadband, and OLEDs in particular produce broad emission spectra.
Narrowing this spontaneous emission toward a monochromatic limit would greatly increase its utility, a goal that has long been a central pursuit in photonics. For example, a narrower emission would achieve more highly saturated colors in LED-based displays.
