Category Physics

A graphen nanoribbon was anchored at the tip of a atomic force microscope and dragged over a gold surface. The observed friction force was extremely low. Credit: University of Basel, Department of Physics

Graphene offers versatile potential for coating machine components and in the field of electronic switches. An international team of researchers led by physicists at the University of Basel have been studying the lubricity of this material on the nanometer scale. Since it produces almost no friction at all, it could drastically reduce energy loss in machines when used as a coating. In future, graphene could be used as an extremely thin coating, resulting in almost zero energy loss between mechanical parts. This is based on superlubricity of modified carbon in the form of graphene...

Silicon chip with nanoscale copper plasmonic components. Credit: Image courtesy of Moscow Institute of Physics and Technology

It was previously believed only gold and silver components have the required properties for this. Copper components are not only just as good as components based on noble metals, but, unlike them, they can easily be implemented in integrated circuits using industry-standard fabrication processes. “This is a kind of revolution – using copper will solve one of the main problems in nanophotonics,” say the authors of the paper. In the very near future copper nanophotonic components will form a basis for the development of energy-efficient light sources, ultra-sensitive sensors, as well as high-performance optoelectronic processors with several thousand cores.

Nanophoton...

In Passive Wi-Fi, power-intensive functions are handled by a single device plugged into the wall. Passive sensors use almost no energy to communicate with routers, phones and other devices.Stock images courtesy of vector.me

With ‘Passive Wi-Fi,’ signals can be transmitted at rates up to 11 megabits/s – rates that are lower than maximum Wi-Fi speeds but are 11 times faster than Bluetooth – and decoded on any of the billions of devices with Wi-Fi connectivity. The new Passive Wi-Fi system also consumes 1,000 times less power than existing energy-efficient wireless communication platforms, such as Bluetooth Low Energy and Zigbee.

The technology has also been named one of the 10 breakthrough technologies of 2016 by MIT Technology Review...

Artistic impression of the sample, the pulse sequence, and the density matrix. Credit: Image by Antti Paraoanu

A superconducting qubit is an artificial atom fabricated on a silicon chip as an electrical circuit made of capacitors and tunnel junctions. This technology is one of the most promising for the realization of quantum computers.

In the experiment, the circuit was operated in a regime where it no longer absorbs or emits electromagnetic waves of certain frequency, as if it would be hiding under an invisibility cloak – hence the term “dark state.” Then, by using a sequence of microwave pulses, the team employed the dark state to realize a transfer of population from the ground energy level to the second energy level, without populating the first energy level...