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Topological insulators are innovative materials that conduct electricity on the surface, but act as insulators on the inside. Physicists at the University of Basel and the Istanbul Technical University have begun investigating how they react to friction. Their experiment shows that the heat generated through friction is significantly lower than in conventional materials. This is due to a new quantum mechanism, the researchers report in the scientific journal Nature Materials.

Thanks to their unique electrical properties, topological insulators promise many innovations in the electronics and computer industries, as well as in the development of quantum computers. The thin surface layer can conduct electricity almost without resistance, resulting in less heat than traditional materials. This makes them of particular interest for electronic components.

“Our measurements clearly show that at certain voltages there is virtually no heat generation caused by electronic friction.” — Dr. Dilek Yildiz

The smallest pieces of nature—individual particles like electrons, for instance—are pretty much interchangeable. An electron is an electron is an electron, regardless of whether it’s stuck in a lab on Earth, bound to an atom in some chalky moon dust or shot out of an extragalactic black hole in a superheated jet. In practice, though, differences in energy, motion or location can make it easy to tell two electrons apart.

One way to test for the similarity of particles like electrons is to bring them together at the same time and place and look for interference—a quantum effect that arises when particles (which can also behave like waves) meet. This interference is important for everything from fundamental tests of quantum physics to the speedy calculations of quantum computers, but creating it requires exquisite control over particles that are indistinguishable.

With an eye toward easing these requirements, researchers at the Joint Quantum Institute (JQI) and the Joint Center for Quantum Information and Computer Science (QuICS) have stretched out multiple photons—the quantum particles of light—and turned three distinct pulses into overlapping quantum waves. The work, which was published recently in the journal Physical Review Letters, restores the interference between photons and may eventually enable a demonstration of a particular kind of quantum supremacy—a clear speed advantage for computers that run on the rules of quantum physics.

Topological insulators are innovative materials that conduct electricity on the surface, but act as insulators on the inside. Physicists at the University of Basel and the Istanbul Technical University have begun investigating how they react to friction. Their experiment shows that the heat generated through friction is significantly lower than in conventional materials. This is due to a new quantum mechanism, the researchers report in the scientific journal Nature Materials.

Thanks to their unique electrical properties, topological insulators promise many innovations in the electronics and computer industries, as well as in the development of quantum computers. The thin surface layer can conduct electricity almost without resistance, resulting in less heat than traditional materials. This makes them of particular interest for electronic components.

Furthermore, in topological insulators, the electronic friction—i.e. the electron-mediated conversion of electrical energy into heat—can be reduced and controlled. Researchers of the University of Basel, the Swiss Nanoscience Institute (SNI) and the Istanbul Technical University have now been able to experimentally verify and demonstrate exactly how the transition from energy to heat through friction behaves—a process known as dissipation.

Three years ago, an outfit called Electric GT (EGT), led by Eric Hutchison, hit the green tech radar by converting a 1978 Ferrari 308 GTS to an electric car. Out went the mid-mounted 2.9-liter V8 making 280 horsepower and 181 pound-feet of torque, in went 48 lithium-ion batteries powering three AC51 HPEVS electric motors that cumulatively produced 465 hp and 330 lb-ft. The company’s relocated from San Diego to Chatsworth, California, and is back on the scopes at Green Car Reports with what it calls an Electric Crate Motor. The innovation repackages the ICE crate motor methodology into a system making EV conversions easier for the weekend enthusiast. EGT promises a plug-and-play system with “high performance and near zero maintenance,” having packaged its one- and two-motor systems into a “motor block” and peripherals that look just like an internal combustion engine.

The block includes everything necessary for the swap to electric except the batteries and the mounting bracket, meaning” motor(s), controller(s), charger(s), sensors, relays and computer systems.” EGT has already designed a number of mounting brackets, and can design others to custom specs. According to the web site, the package is “pre-engineered, pre-built, and pre-tested,” so installation takes five steps: Bolt in the block, install the wiring harness and cooling system, connect the AC and DC power leads with the OEM-level touch-safe connectors, and route the internal cooling pump to a heat exchanger. Voila, silent running. Every e-crate motor comes with an installation manual, EGT provides tech support, and auxiliaries like electric AC compressors and heaters can be optioned.

Physicists and materials scientists have developed a compact optical device containing vertically stacked metasurfaces that can generate microscopic text and full-color holograms for encrypted data storage and color displays. Yueqiang Hu and a research team in Advanced Design and Manufacturing for Vehicle Body in the College of Mechanical and Vehicle Engineering in China implemented a 3D integrated metasurface device to facilitate miniaturization of the optical device. Using metasurfaces with ultrathin and compact characteristics, the research team designed optical elements by engineering the wavefront of light at the subwavelength scale. The metasurfaces possessed great potential to integrate multiple functions into the miniaturized optoelectronic systems. The work is now published on Light: Science & Applications.

Since existing research on multiplexing in the 2-D plane remains to fully incorporate capabilities of metasurfaces for multi-tasking, in the present work, the team demonstrated a 3D integrated metasurface device. For this, they stacked a hologram metasurface on a monolithic Fabry-Pérot (FP) cavity-based color filter microarray to achieve simultaneous cross-talk, polarization-independent and highly efficient full-color holography and microprint functions. The dual function of the device outlined a new scheme for data recording, security, encryption color displays and information processing applications. The work on 3D integration can be extended to establish flat multi-tasking optical systems that include a variety of functional metasurface layers.

Metasurfaces open a new direction in optoelectronics, allowing researchers to design optical elements by shaping the wavefront of electromagnetic waves relative to size, shape and arrangement of structures at the subwavelength. Physicists have engineered a variety of metasurface-based devices including lenses, polarization converters, holograms and orbital angular momentum generators (OAM). They have demonstrated the performance of metasurface-based devices to even surpass conventional refractive elements to construct compact optical devices with multiple functions. Such devices are, however, withheld by shortcomings due to a reduced efficiency of plasmonic nanostructures, polarization requirements, large crosstalk and complexity of the readout for multiwavelength and broadband optical devices. Research teams can therefore stack 3D metasurface-based devices with different functions in the vertical direction to combine the advantages of each device.

Razer has announced a new iteration of its Blade 15 Advanced gaming laptop. Its new, clickier keyboard might be the biggest change. Otherwise, much of what this configuration offers isn’t new for Razer.

Researchers have successfully used sound waves to control quantum information in a single electron, a significant step towards efficient, robust quantum computers made from semiconductors.

The international team, including researchers from the University of Cambridge, sent high-frequency sound waves across a modified semiconductor device to direct the behaviour of a single electron, with efficiencies in excess of 99 percent. The results are reported in the journal Nature Communications.

A quantum computer would be able to solve previously unsolvable computational problems by taking advantage of the strange behaviour of particles at the subatomic scale, and quantum phenomena such as entanglement and superposition. However, precisely controlling the behaviour of quantum particles is a mammoth task.

Researchers from Aalto University and VTT Technical Research Centre of Finland have built a super-sensitive bolometer, a type of thermal radiation detector. The new radiation detector, made of a gold-palladium mixture makes it easier to measure the strength of electromagnetic radiation in real time. Bolometers are used widely in thermal cameras in the construction industry and in satellites to measure cosmic radiation.

The new developments may help bolometers find their way to quantum computers. If the new radiation detector manages to function as well in space as it does in the laboratory, it can also be used to measure cosmic microwave background radiation in space more accurately.

“The new detector is extremely sensitive, and its noise level—how much the signal bounces around the correct value, is only one tenth of the noise of any other bolometer. It is also a hundred times faster than previous low-noise radiation detectors,” says Mikko Möttönen, who works as a joint Professor of Quantum Technology at Aalto University and VTT.

Researchers at EPFL have created a metallic microdevice in which they can define and tune patterns of superconductivity. Their discovery, which holds great promise for quantum technologies of the future, has just been published in Science.

In superconductors, electrons travel with no resistance. This phenomenon currently only occurs at very low temperatures. There are many practical applications, such as magnetic resonance imaging (MRI). Future technologies, however, will harness the total synchrony of electronic behavior in superconductors—a property called the phase. There is currently a race to build the world’s first quantum computer, which will use phases to perform calculations. Conventional superconductors are very robust and hard to influence, and the challenge is to find new materials in which the superconducting state can be easily manipulated in a device.

EPFL’s Laboratory of Quantum Materials (QMAT), headed by Philip Moll, has been working on a specific group of unconventional superconductors known as heavy fermion materials. The QMAT scientists, as part of a broad international collaboration between EPFL, the Max Planck Institute for Chemical Physics of Solids, the Los Alamos National Laboratory and Cornell University, made a surprising discovery about one of these materials, CeIrIn₅.