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Apr 17, 2023

Washing with Vortices

Posted by in category: materials

A fluid flow called a vortex ring can effectively remove oil from a thin, porous material and can clean both surfaces at once.

Apr 17, 2023

Sorting Ions

Posted by in category: sustainability

Researchers predict that a “flashing” electric ratchet could separate same-charge ions by their diffusion coefficients, a possibility that could improve the energy efficiency of processes such as water desalination and purification.

Apr 17, 2023

Disentangling the Sun’s Impact on Cosmic Rays

Posted by in categories: cosmology, particle physics

An instrument on the International Space Station has revealed new information about how the Sun’s magnetic field affects cosmic rays on their way to Earth.

Galactic cosmic rays (GCRs) are highly energetic charged particles that are produced through various acceleration mechanisms in astrophysical objects such as supernova remnants. These particles propagate through the Galaxy and can reach the heliosphere, a region dominated by plasma originating from the Sun. Within the heliosphere, GCRs interact with the turbulent plasma environment in a way that decreases their flux, causing them to diffuse in space and to lose energy [1]. Most of the impact of this “solar modulation” on GCRs is independent of particle charge. But GCR drift is also influenced by large-scale gradients in, and curvatures of, the heliospheric magnetic field and by the current sheet—a tenuous structure that separates the heliosphere into regions of opposite magnetic-field polarity [2].

Apr 17, 2023

Educators Needed for a Quantum Future

Posted by in categories: economics, education, employment, government, quantum physics

To build a workforce that can meet the expected future demand in the quantum sector, we need to train many more quantum-literate educators and marshal support for them.

In 2018 the US federal government passed the National Quantum Initiative Act, a program designed to accelerate the country’s quantum research and development activities. In the next decade, quantum information science and quantum technologies are expected to have a significant impact on the US economy, as well as on that of other countries. To fulfill that promise, the US will need a “quantum-capable” workforce that is conversant with the core aspects of quantum technologies and is large enough to meet the expected demand. But even now, as quantum-career opportunities are just starting to appear, supply falls behind demand; according to a 2022 report, there is currently only around one qualified candidate for every three quantum job openings [1]. We call for education institutions and funding agencies to invest significantly in workforce development efforts to prevent the worsening of this dearth.

Most of today’s jobs in quantum information science and technology (QIST) require detailed knowledge and skills that students typically gain in graduate-level programs [2]. As the quantum industry matures from having a research and development focus toward having a deployment focus, this requirement will likely relax. The change is expected to increase the proportion of QIST jobs compatible with undergraduate-level training. However, 86% of QIST-focused courses currently take place at PhD-granting research institutions [3]. Very few other undergraduate institutions offer opportunities to learn about the subject. To meet the future need, we believe that aspect needs to change with QIST education being incorporated into the curricula at predominantly undergraduate institutions and community colleges in the US. However, adding QIST classes to the curricula at these institutions will be no easy task.

Apr 17, 2023

The comprehensive characterization of hydrogen at ultra-high pressures

Posted by in categories: materials, physics

Physicists and material scientists have been trying to metallize hydrogen for many decades, but they have not yet succeeded. In 1968, British physicist Neil Ashcroft predicted that atomic metallic hydrogen would be a high-temperature semiconductor.

Most recent studies also suggested that this elusive and hypothetical form of hydrogen would also conduct electricity with no resistance when its temperature exceeds that of boiling water. This prediction ultimately paved the way for the discovery of high-temperature superconductivity in hydrides (i.e., compounds containing hydrogen and a metal).

Researchers at Sapienza University of Rome, Sorbonne University, CNRS, and the International School for Advanced Studies (SISSA) have recently carried out a study aimed at thoroughly characterizing the behavior and properties of hydrogen at high pressures. Their paper, published in Nature Physics, outlines a highly accurate phase diagram of high-pressure hydrogen, which could inform ongoing efforts aimed at creating atomic metallic hydrogen.

Apr 17, 2023

Study demonstrates the non-volatile electrical control of a 2D magnetic insulator using a thin ferroelectric polymer

Posted by in categories: computing, materials

Two-dimensional (2D) magnetic insulators, which are electrically insulating materials with long-range magnetic order, could be used to fabricate compact magneto-electric or magneto-optical devices. Efficiently and reliably controlling the properties of these atomically thin magnets through electrical means, however, has so far proved to be highly challenging, as the materials’ charge levels often cannot be largely adjusted and their crystal fields cannot be considerably altered using external electric fields.

Researchers at University of Maryland and their collaborators recently devised a new strategy that could be used to efficiently control 2D magnetic insulators. This strategy, outlined in a paper in Nature Electronics, relies on the use of a thin ferroelectric polymer that can modulate the 2D materials’ magnetic responses.

“When it comes to , people are primarily pursuing a smaller form factor (relating to higher integration density, which means more devices can be integrated on the unit area/volume of a chip), lower energy consumption, and higher performance,” Cheng Gong, the lead principal investigator for the study, told Tech Xplore.

Apr 17, 2023

Solar sails could guide interplanetary travel, says new study

Posted by in category: space

Space travel has brought us to our next-door neighbor, the moon, and to the depths of our larger solar community inhabited by giants such as Saturn and Jupiter.

In 1982, Voyager 2 whisked past Uranus closer than any other spacecraft has since, and now is sailing—46 years after its launch—through the constellation of Pavo, some 179 from Earth.

But there have been few comparable satellite missions in recent years. Cost is the main obstacle, but time frame is also a factor. The design for such long journeys takes years to calculate, and planning and construction of a space vehicle would take about a decade. Factoring in the time a satellite would require to reach distant targets means our next peek into the stars will likely not come any time soon.

Apr 17, 2023

Quantum light source goes fully on-chip, bringing scalability to the quantum cloud

Posted by in categories: computing, internet, quantum physics

An international team of researchers from Leibniz University Hannover (Germany), the University of Twente (Netherlands), and the start-up company QuiX Quantum has presented an entangled quantum light source fully integrated for the first time on a chip. The results of the study were published in the journal Nature Photonics.

“Our breakthrough allowed us to shrink the source size by a factor of more than 1,000, allowing reproducibility, stability over a longer time, scaling, and potentially mass-production. All these characteristics are required for real-world applications such as ,” says Prof. Dr. Michael Kues, head of the Institute of Photonics, and board member of the Cluster of Excellence PhoenixD at Leibniz University Hannover.

Quantum bits () are the basic building blocks of quantum computers and the quantum internet. Quantum light sources generate light quanta (photons) that can be used as . On-chip photonics has become a leading platform for processing optical quantum states as it is compact, robust, and allows to accommodate and arrange many elements on a . Here, light is directed on the chip through extremely compact structures, which are used to build photonic quantum computing systems. These are already accessible today through the cloud. Scalably implemented, they could solve tasks that are inaccessible to conventional computers due to their limited computing capacities. This superiority is referred to as quantum advantage.

Apr 17, 2023

Physicists discover first transformable nanoscale electronic devices

Posted by in categories: mobile phones, nanotechnology, quantum physics

The nanoscale electronic parts in devices like smartphones are solid, static objects that once designed and built cannot transform into anything else. But University of California, Irvine physicists have reported the discovery of nanoscale devices that can transform into many different shapes and sizes even though they exist in solid states.

It’s a finding that could fundamentally change the nature of , as well as the way scientists research atomic-scale quantum materials. The study is published in Science Advances.

“What we discovered is that for a particular set of materials, you can make nanoscale electronic devices that aren’t stuck together,” said Javier Sanchez-Yamagishi, an assistant professor of physics & astronomy whose lab performed the new research. “The parts can move, and so that allows us to modify the size and shape of a device after it’s been made.”

Apr 17, 2023

Physicists find unusual waves in nickel-based magnet

Posted by in category: particle physics

Perturbing electron spins in a magnet usually results in excitations called “spin waves” that ripple through the magnet like waves on a pond that’s been struck by a pebble. In a new study, Rice University physicists and their collaborators have discovered dramatically different excitations called “spin excitons” that can also “ripple” through a nickel-based magnet as a coherent wave.

In a study published in Nature Communications, the researchers reported finding unusual properties in nickel molybdate, a layered magnetic crystal. Subatomic particles called electrons resemble miniscule magnets, and they typically orient themselves like compass needles in relation to magnetic fields. In experiments where neutrons were scattered from magnetic nickel ions inside the crystals, the researchers found that two outermost electrons from each nickel ion behaved differently. Rather than aligning their spins like compass needles, the two canceled one another in a phenomenon physicists call a spin singlet.

“Such a substance should not be a magnet at all,” said Rice’s Pengcheng Dai, corresponding author of the study. “And if a neutron scatters off a given nickel ion, the excitations should remain local and not propagate through the sample.”