Understanding electron transport in graphene nanoribbons

Graphene is a modern wonder material possessing unique properties of strength, flexibility and conductivity whilst being abundant and remarkably cheap to produce, lending it to a multitude of useful applications -- especially true when these 2D atom-thick sheets of carbon are split into narrow strips known as Graphene Nanoribbons (GNRs). New research published in EPJ Plus, authored by Kristians Cernevics, Michele Pizzochero, and Oleg V. Yazyev, Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland, aims to better understand the electron transport properties of GNRs and how they are affected by bonding with aromatics. This is a key step in designing technology such chemosensors. "Graphene nanoribbons -- strips of graphene just few nanometres wide -- are a new and exciting class of nanostructures that have emerged as potential building blocks for…
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Stanford technology predicts the slow death of lithium-ion batteries

Batteries fade as they age, slowly losing power and storage capacity. As in people, aging plays out differently from one battery to another, and it's next to impossible to measure or model all of the interacting mechanisms that contribute to decline. As a result, most of the systems used to manage charge levels wisely and to estimate driving range in electric cars are nearly blind to changes in the battery's internal workings. Instead, they operate more like a doctor prescribing treatment without knowing the state of a patient's heart and lungs, and the particular ways that environment, lifestyle, stress and luck have ravaged or spared them. If you've kept a laptop or phone for enough years, you may have seen where this leads firsthand: Estimates of remaining battery life tend…
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Memory in a metal, enabled by quantum geometry

The emergence of artificial intelligence and machine learning techniques is changing the world dramatically with novel applications such as internet of things, autonomous vehicles, real-time imaging processing and big data analytics in healthcare. In 2020, the global data volume is estimated to reach 44 Zettabytes, and it will continue to grow beyond the current capacity of computing and storage devices. At the same time, the related electricity consumption will increase 15 times by 2030, swallowing 8% of the global energy demand. Therefore, reducing energy consumption and increasing speed of information storage technology is in urgent need. Berkeley researchers led by HKU President Professor Xiang Zhang when he was in Berkeley, in collaboration with Professor Aaron Lindenberg's team at Stanford University, invented a new data storage method: They make odd numbered…
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Microscopic robots ‘walk’ thanks to laser tech

A Cornell University-led collaboration has created the first microscopic robots that incorporate semiconductor components, allowing them to be controlled -- and made to walk -- with standard electronic signals. These robots, roughly the size of paramecium, provide a template for building even more complex versions that utilize silicon-based intelligence, can be mass produced, and may someday travel through human tissue and blood. The collaboration is led by Itai Cohen, professor of physics, Paul McEuen, the John A. Newman Professor of Physical Science and their former postdoctoral researcher Marc Miskin, who is now an assistant professor at the University of Pennsylvania. The walking robots are the latest iteration, and in many ways an evolution, of Cohen and McEuen's previous nanoscale creations, from microscopic sensors to graphene-based origami machines. The new robots…
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Artificial materials for more efficient electronics

We are surrounded by electronic devices. Transistors are used to power telephones, computers, televisions, hi-fi systems and game consoles as well as cars, airplanes and the like. Today's silicon-based electronics, however, consume a substantial and ever-increasing share of the world's energy. A number of researchers are exploring the properties of materials that are more complex than silicon but that show promise for the electronic devices of tomorrow -- and that are less electricity-hungry. In keeping with this approach, scientists from the University of Geneva (UNIGE) have been working in collaboration with the Swiss Federal Institute of Technology in Lausanne (EPFL), the University of Zurich, the Flatiron Institute of New York and the University of Li├Ęge. The scientists have discovered a hitherto-unknown physical phenomenon in an artificial material made up of…
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