Aurelia Butler

A joint group of scientists from Finland, Russia, China and the USA have demonstrated that temperature difference can be used to entangle pairs of electrons in superconducting structures. The experimental discovery, published in Nature Communications, promises powerful applications in quantum devices, bringing us one step closer towards applications of the second quantum revolution.
The team, led by Professor Pertti Hakonen from Aalto University, has shown that the thermoelectric effect provides a new method for producing entangled electrons in a new device. “Quantum entanglement is the cornerstone of the novel quantum technologies. This concept, however, has puzzled many physicists over the years, including Albert Einstein who worried a lot about the spooky interaction at a distance that it causes,” says Prof. Hakonen.
In quantum computing, entanglement is used to fuse individual quantum systems into one, which exponentially increases their total computational capacity. “Entanglement can also be used in quantum cryptography, enabling the secure exchange of information over long distances,” explains Prof. Gordey Lesovik, from the Moscow Institute of Physics and Technology, who has acted several times as a visiting professor at Aalto University School of Science. Given the significance of entanglement to quantum technology, the ability to create entanglement easily and controllably is an important goal for researchers.
The researchers designed a device where a superconductor was layered withed graphene and metal electrodes. “Superconductivity is caused by entangled pairs of electrons called “cooper pairs.” Using a temperature difference, we cause them to split, with each electron then moving to different normal metal electrode,” explains doctoral candidate Nikita Kirsanov, from Aalto University. “The resulting electrons remain entangled despite being separated for quite long distances.”
Along with the practical implications, the work has significant fundamental importance. The experiment has shown that the process of Cooper pair splitting works as a mechanism for turning temperature difference into correlated electrical signals in superconducting structures. The developed experimental scheme may also become a platform for original quantum thermodynamical experiments.

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In a money-saving revelation for organizations inclined to invest in specialized information technology to support the process of idea generation, new research suggests that even non-specialized, everyday organizational IT can encourage employees’ creativity.
Recently published in the journal Information and Organization, these findings from Dorit Nevo, an associate professor in the Lally School of Management at Rensselaer Polytechnic Institute, show standard IT can be used for innovation. Furthermore, this is much more likely to happen when the technology is in the hands of employees who are motivated to master technology, understand their role in the organization, are recognized for their efforts, and are encouraged to develop their skills.
“What this study reveals is that innovation is found not just by using technology specifically created to support idea-generation,” Nevo said. “Creativity comes from both the tool and the person who uses it.”
Most businesses and organizations use common computer technologies, such as business analytics programs, knowledge management systems, and point-of-sale systems, to enable employees to complete basic job responsibilities. Nevo wanted to know if this standard IT could also be used by employees to create new ideas in the front end of the innovation process, where ideas are generated, developed, and then championed.
By developing a theoretically grounded model to examine IT-enabled innovation in an empirical study, Nevo found that employees who are motivated to master IT can use even standard technology as a creativity tool, increasing the return on investment on the technologies companies already have in-house.
“An organization can get a lot more value out of their IT technology if they let the right people use them and then support them,” Nevo said. “This added value will, in turn, save organizations money because they don’t always have to invest in specialized technology in order for their employees to generate solutions to work-related issues or ideas for improvement in the workplace. You just have to trust your employees to be able to innovate with the technologies you have.”

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Materials provided by Rensselaer Polytechnic Institute. Original written by Jeanne Hedden Gallagher. Note: Content may be edited for style and length. More

Whenever an organism develops and forms organs, a tumour creates metastases or the immune system becomes active in inflammation, cells migrate within the body. As they do, they interact with surrounding tissues which influence their function. The migrating cells react to biochemical signals, as well as to biophysical properties of their environment, for example whether a tissue is soft or stiff. Gaining detailed knowledge about such processes provides scientists with a basis for understanding medical conditions and developing treatment approaches.
A team of biologists and mathematicians at the Universities of Münster and Erlangen-Nürnberg has now developed a new method for analysing cell migration processes in living organisms. The researchers investigated how primordial germ cells whose mode of locomotion is similar to other migrating cell types, including cancer cells, behave in zebrafish embryos when deprived of their biochemical guidance cue. The team developed new software that makes it possible to merge three-dimensional microscopic images of multiple embryos in order to recognise patterns in the distribution of cells and thus highlight tissues that influence cell migration. With the help of the software, researchers determined domains that the cells either avoided, to which they responded by clustering, or in which they maintained their normal distribution. In this way, they identified a physical barrier at the border of the organism’s future backbone where the cells changed their path. “We expect that our experimental approach and the newly developed tools will be of great benefit in research on developmental biology, cell biology and biomedicine,” explains Prof Dr Erez Raz, a cell biologist and project director at the Center for Molecular Biology of Inflammation at Münster University. The study has been published in the journal Science Advances.
Details on methods and results
For their investigations, the researchers made use of primordial germ cells in zebrafish embryos. Primordial germ cells are the precursors of sperm and egg cells and, during the development of many organisms, they migrate to the place where the reproductive organs form. Normally, these cells are guided by chemokines — i.e. attractants produced by surrounding cells that initiate signalling pathways by binding to receptors on the primordial germ cells. By genetically modifying the cells, the scientists deactivated the chemokine receptor Cxcr4b so that the cells remained motile but no longer migrated in a directional manner. “Our idea was that the distribution of the cells within the organism — when not being controlled by guidance cues — can provide clues as to which tissues influence cell migration, and then we can analyse the properties of these tissues,” explains ?ukasz Truszkowski, one of the three lead authors of the study.
“To obtain statistically significant data on the spatial distribution of the migrating cells, we needed to study several hundred zebrafish embryos, because at the developmental stage at which the cells are actively migrating, a single embryo has only around 20 primordial germ cells,” says Sargon Groß-Thebing, also a first author and, like his colleague, a PhD student in the graduate programme of the Cells in Motion Interfaculty Centre at the University of Münster. In order to digitally merge the three-dimensional data of multiple embryos, the biology researchers joined forces with a team led by the mathematician Prof Dr Martin Burger, who was also conducting research at the University of Münster at that time and is now continuing the collaboration from the University of Erlangen-Nürnberg. The team developed a new software tool that pools the data automatically and recognises patterns in the distribution of primordial germ cells. The challenge was to account for the varying sizes and shapes of the individual zebrafish embryos and their precise three-dimensional orientation in the microscope images.
The software named “Landscape” aligns the images captured from all the embryos with each other. “Based on a segmentation of the cell nuclei, we can estimate the shape of the embryos and correct for their size. Afterwards, we adjust the orientation of the organisms,” says mathematician Dr Daniel Tenbrinck, the third lead author of the study. In doing so, a tissue in the midline of the embryos serves as a reference structure which is marked by a tissue-specific expression of the so-called green fluorescent protein (GFP). In technical jargon the whole process is called image registration. The scientists verified the reliability of their algorithms by capturing several images of the same embryo, manipulating them with respect to size and image orientation, and testing the ability of the software to correct for the manipulations. To evaluate the ability of the software to recognise cell-accumulation patterns, they used microscopic images of normally developing embryos, in which the migrating cells accumulate at a known specific location in the embryo. The researchers also demonstrated that the software can be applied to embryos of another experimental model, embryos of the fruit fly Drosophila, which have a shape that is different from that of zebrafish embryos.
Using the new method, the researchers analysed the distribution of 21,000 primordial germ cells in 900 zebrafish embryos. As expected, the cells lacking a chemokine receptor were distributed in a pattern that differs from that observed in normal embryos. However, the cells were distributed in a distinct pattern that could not be recognised by monitoring single embryos. For example, in the midline of the embryo, the cells were absent. The researchers investigated that region more closely and found it to function as a physical barrier for the cells. When the cells came in contact with this border, they changed the distribution of actin protein within them, which in turn led to a change of cell migration direction and movement away from the barrier. A deeper understanding of how cells respond to physical barriers may be relevant in metastatic cancer cells that invade neighbouring tissues and where this process may be disrupted.

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Social media misinformation can negatively influence people’s attitudes about vaccine safety and effectiveness, but credible organizations — such as research universities and health institutions — can play a pivotal role in debunking myths with simple tags that link to factual information, University of California, Davis, researchers, suggest in a new study.
Researchers found that fact-check tags located immediately below or near a post can generate more positive attitudes toward vaccines than misinformation alone, and perceived source expertise makes a difference. “In fact, fact-checking labels from health institutions and research universities were seen as more ‘expert’ than others, indirectly resulting in more positive attitudes toward vaccines,” said Jingwen Zhang, assistant professor of communication and lead author of the study.
The findings were published online Wednesday, Jan. 6, in the journal Preventive Medicine.
Has implications for COVID-19
The data was collected in 2018 — before the COVID-19 pandemic — but the study’s results could influence public communications about COVID-19 vaccines, researchers said.
“The most important thing I learned from this paper is that fact checking is effective…giving people a simple label can change their attitude,” Zhang said. “Secondly, I am calling for more researchers and scientists to engage in public health and science communications. We need to be more proactive. We are not using our power right now.”
While there is a strong consensus in the medical community that vaccines are safe, cost-effective and successful in preventing diseases, widespread vaccine hesitancy has resurged in many countries, the study said. The United States has faced issues with lower-than-preferred vaccine participation for influenza and even measles, which medical experts blamed for a 2019 measles outbreak. “Because both individuals and groups can post misinformation, such as false claims about vaccines, social media have played a role in spreading misinformation,” Zhang said.

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Study authors tested the effects of simple fact-checking labels with 1,198 people nationwide who showed different levels of vaccine hesitancy. In the experiment, researchers used multiple misinformation messages covering five vaccine types and five categories of 13 different fact-checking sources. They avoided any explanations that repeated the false information.
Using a mock twitter account, one post, for example, consisted of a misinformation claim on a specific vaccine and a picture of a vaccine bottle. It read: “According to a US Vaccine Adverse Events Reporting System (VAERS) there were 93,000 adverse reactions to last year’s Flu Shot including 1,080 deaths & 8,888 hospitalizations.”
Researchers then used alternating fact-checking labels from various sources in media, health organizations such as the Centers for Disease Control and Prevention, Johns Hopkins University, and algorithms. One read, for example, “This post is falsified. Fact-checked by the Centers For Disease Control. Learn why this is falsified.”
The results showed that those exposed to fact-checking labels were more likely to develop more positive attitudes toward vaccines than misinformation alone. Further, the labels’ effect was not moderated by vaccine skepticism, the type of vaccine misinformation or political ideology.
“What approaches are most effective at targeting vaccine misinformation on social media among users unlikely to visit fact-checking websites or engage with thorough corrections?” researchers asked in the paper. “This project shows that seeing a fact-checking label immediately below a misinformation post can make viewers more favorable toward vaccines.”
She explained that a tag could be as simple as a reply to a misinforming tweet that explains the information is false, and links to credible information at a university or institutional web site.
Ideally, she said, tagging should be done by social media companies such as Facebook and Twitter. She said social media companies are working with entities, such as the WHO, to correct misinformation. “We are headed in the right direction, but more needs to happen,” she said.
Study co-authors included Magdalena Wojcieszak, associate professor of communication, and doctoral students Jieyu Ding Featherstone (Department of Communication) and Christopher Calabrese (Department of Public Health Sciences), all of UC Davis. More

An international team of researchers led by Swinburne University of Technology has demonstrated the world’s fastest and most powerful optical neuromorphic processor for artificial intelligence (AI), which operates faster than 10 trillion operations per second (TeraOPs/s) and is capable of processing ultra-large scale data.
Published in the journal Nature, this breakthrough represents an enormous leap forward for neural networks and neuromorphic processing in general.
Artificial neural networks, a key form of AI, can ‘learn’ and perform complex operations with wide applications to computer vision, natural language processing, facial recognition, speech translation, playing strategy games, medical diagnosis and many other areas. Inspired by the biological structure of the brain’s visual cortex system, artificial neural networks extract key features of raw data to predict properties and behaviour with unprecedented accuracy and simplicity.
Led by Swinburne’s Professor David Moss, Dr Xingyuan (Mike) Xu (Swinburne, Monash University) and Distinguished Professor Arnan Mitchell from RMIT University, the team achieved an exceptional feat in optical neural networks: dramatically accelerating their computing speed and processing power.
The team demonstrated an optical neuromorphic processor operating more than 1000 times faster than any previous processor, with the system also processing record-sized ultra-large scale images — enough to achieve full facial image recognition, something that other optical processors have been unable to accomplish.
“This breakthrough was achieved with ‘optical micro-combs’, as was our world-record internet data speed reported in May 2020,” says Professor Moss, Director of Swinburne’s Optical Sciences Centre and recently named one of Australia’s top research leaders in physics and mathematics in the field of optics and photonics by The Australian.

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While state-of-the-art electronic processors such as the Google TPU can operate beyond 100 TeraOPs/s, this is done with tens of thousands of parallel processors. In contrast, the optical system demonstrated by the team uses a single processor and was achieved using a new technique of simultaneously interleaving the data in time, wavelength and spatial dimensions through an integrated micro-comb source.
Micro-combs are relatively new devices that act like a rainbow made up of hundreds of high-quality infrared lasers on a single chip. They are much faster, smaller, lighter and cheaper than any other optical source.
“In the 10 years since I co-invented them, integrated micro-comb chips have become enormously important and it is truly exciting to see them enabling these huge advances in information communication and processing. Micro-combs offer enormous promise for us to meet the world’s insatiable need for information,” Professor Moss says.
“This processor can serve as a universal ultrahigh bandwidth front end for any neuromorphic hardware — optical or electronic based — bringing massive-data machine learning for real-time ultrahigh bandwidth data within reach,” says co-lead author of the study, Dr Xu, Swinburne alum and postdoctoral fellow with the Electrical and Computer Systems Engineering Department at Monash University.
“We’re currently getting a sneak-peak of how the processors of the future will look. It’s really showing us how dramatically we can scale the power of our processors through the innovative use of microcombs,” Dr Xu explains.
RMIT’s Professor Mitchell adds, “This technology is applicable to all forms of processing and communications — it will have a huge impact. Long term we hope to realise fully integrated systems on a chip, greatly reducing cost and energy consumption.”
“Convolutional neural networks have been central to the artificial intelligence revolution, but existing silicon technology increasingly presents a bottleneck in processing speed and energy efficiency,” says key supporter of the research team, Professor Damien Hicks, from Swinburne and the Walter and Elizabeth Hall Institute.
He adds, “This breakthrough shows how a new optical technology makes such networks faster and more efficient and is a profound demonstration of the benefits of cross-disciplinary thinking, in having the inspiration and courage to take an idea from one field and using it to solve a fundamental problem in another.” More

Using synchrotron radiation at SPring-8 — a large-scale synchrotron radiation facility — Tohoku University, Toshiba Corporation, and the Japan Synchrotron Radiation Research Institute (JASRI) have successfully imaged the magnetization dynamics of a hard disk drive (HDD) write head for the first time, with a precision of one ten-billionth of a second. The method makes possible precise analysis of write head operations, accelerating the development of the next-generation write heads and further increasing HDD capacity.
Details of the research were published in the Journal of Applied Physics on October 6 and presented at the 44th Annual Conference on Magnetics in Japan, on December 14.
International Data Corporation predicts a five-fold increase in the volume of data generated worldwide in the seven years between 2018 and 2025. HDDs continue to serve as the primary data storage devices in use, and in 2020 the annual total capacity of shipped HDDs is expected to exceed one zettabyte (1021 bytes), with sales reaching $20 billion. Securing further increases in HDD capacity and higher data transfer rates with logical write head designs requires an exhaustive and accurate understanding of write head operations.
There are, however, high barriers to achieving this: current write heads have a very fine structure, with dimensions of less than 100 nanometers. Magnetization reversal occurs in less than a nanosecond, rendering experimental observations of write head dynamics difficult. Instead, the write head analysis has been conducted by simulations of magnetization dynamics, or done indirectly by evaluating the write performance on the magnetic recording media. Both approaches have their drawbacks, and there is clear demand for a new method capable of capturing the dynamics of a write head precisely.
Tohoku University, Toshiba, and JASRI used the scanning soft X-ray magnetic circular dichroism microscope installed on the BL25SU beamline at SPring-8 to develop a new analysis technology for HDD write heads.
The new technology realizes time-resolved measurements through synchronized timing control, in which a write head is operated at an interval of one-tenth of the cycle of the periodic X-ray pulses generated from the SPring-8 storage ring. Simultaneously, focused X-rays scan the medium-facing surface of a write head, and magnetic circular dichroism images temporal changes in the magnetization. This achieves temporal resolution of 50 picoseconds and spatial resolution of 100 nanometers, enabling analyses of the fine structures and fast write head operation. This method has the potential to achieve even higher resolutions by improving the focusing optics for the X-rays.
The development team used the new technology to obtain the time evolution of the magnetization images during reversal of the write head. The imaging revealed that magnetization reversal of the main pole is completed within a nanosecond and that spatial patterns from magnetization appear in the shield area in response to the main pole reversal. No previous research into write head operations has achieved such high spatial and temporal resolutions, and the use of this approach is expected to support high-precision analyses of write head operations, contributing to the development of the next-generation write heads and the further improvements in HDD performance.
Toshiba is currently developing energy-assisted magnetic recording technologies for next-generation HDD and aims to apply the developed analysis method and the knowledge obtained about write head operations to the development of a write head for energy-assisted magnetic recording.

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They are as thin as a hair, only a hundred thousand times thinner — so-called two-dimensional materials, consisting of a single layer of atoms, have been booming in research for years. They became known to a wider audience when two Russian-British scientists were awarded the Nobel Prize in Physics in 2010 for the discovery of graphene, a building block of graphite. The special feature of such materials is that they possess novel properties that can only be explained with the help of the laws of quantum mechanics and that may be relevant for enhanced technologies. Researchers at the University of Bonn (Germany) have now used ultracold atoms to gain new insights into previously unknown quantum phenomena. They found out that the magnetic orders between two coupled thin films of atoms compete with each other. The study has been published in the journal Nature.
Quantum systems realize very unique states of matter originating from the world of nanostructures. They facilitate a wide variety of new technological applications, e.g. contributing to secure data encryption, introducing ever smaller and faster technical devices and even enabling the development of a quantum computer. In the future, such a computer could solve problems which conventional computers cannot solve at all or only over a long period of time.
How unusual quantum phenomena arise is still far from being fully understood. To shed light on this, a team of physicists led by Prof. Michael Köhl at the Matter and Light for Quantum Computing Cluster of Excellence at the University of Bonn are using so-called quantum simulators, which mimic the interaction of several quantum particles — something that cannot be done with conventional methods. Even state-of-the-art computer models cannot calculate complex processes such as magnetism and electricity down to the last detail.
Ultracold atoms simulate solids
The simulator used by the scientists consists of ultracold atoms — ultracold because their temperature is only a millionth of a degree above absolute zero. The atoms are cooled down using lasers and magnetic fields. The atoms are located in optical lattices, i.e. standing waves formed by superimposing laser beams. This way, the atoms simulate the behavior of electrons in a solid state. The experimental setup allows the scientists to perform a wide variety of experiments without external modifications.
Within the quantum simulator, the scientists have, for the first time, succeeded in measuring the magnetic correlations of exactly two coupled layers of a crystal lattice. “Via the strength of this coupling, we were able to rotate the direction in which magnetism forms by 90 degrees — without changing the material in any other way,” first authors Nicola Wurz and Marcell Gall, doctoral students in Michael Köhl’s research group, explain.
To study the distribution of atoms in the optical lattice, the physicists used a high-resolution microscope with which they were able to measure magnetic correlations between the individual lattice layers. In this way, they investigated the magnetic order, i.e. the mutual alignment of the atomic magnetic moments in the simulated solid state. They observed that the magnetic order between layers competed with the original order within a single layer, concluding that the more strongly layers were coupled, the more strongly correlations formed between the layers. At the same time, correlations within individual layers were reduced.
The new results make it possible to better understand the magnetism propagating in the coupled layer systems at the microscopic level. In the future, the findings are to help make predictions about material properties and achieve new functionalities of solids, among other things. Since, for example, high-temperature superconductivity is closely linked to magnetic couplings, the new findings could, in the long run, contribute to the development of new technologies based on such superconductors.
The Matter and Light for Quantum Computing (ML4Q) Cluster of Excellence
The Matter and Light for Quantum Computing (ML4Q) Cluster of Excellence is a research cooperation by the universities of Cologne, Aachen and Bonn, as well as the Forschungszentrum Jülich. It is funded as part of the Excellence Strategy of the German federal and state governments. The aim of ML4Q is to develop new computing and networking architectures using the principles of quantum mechanics. ML4Q builds on and extends the complementary expertise in the three key research fields: solid-state physics, quantum optics, and quantum information science.
The Cluster of Excellence is embedded in the Transdisciplinary Research Area “Building Blocks of Matter and Fundamental Interactions” at the University of Bonn. In six different TRAs, scientists from a wide range of faculties and disciplines come together to work on future-relevant research topics.

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Ultrasmall integrated circuits have revolutionized mobile phones, home appliances, cars, and other everyday technologies. To further miniaturize electronics and enable advanced functions, circuits must be reliably fabricated in three dimensions. Achieving ultrafine 3D shape control by etching into silicon is difficult because even atomic-scale damage reduces device performance. Researchers at Nara Institute of Science and Technology (NAIST) report, in a new study seen in Crystal Growth and Design, silicon etched to adopt the shape of atomically smooth pyramids. Coating these silicon pyramids with a thin layer of iron imparts magnetic properties that until now were only theoretical.
NAIST researcher and senior author of the study Ken Hattori is widely published in the field of atomically controlled nanotechnology. One focus of Hattori’s research is in improving the functionality of silicon-based technology.
“Silicon is the workhorse of modern electronics because it can act as a semiconductor or an insulator, and it’s an abundant element. However, future technological advances require atomically smooth device fabrication in three dimensions,” says Hattori.
A combination of standard dry etching and chemical etching is necessary to fabricate arrays of pyramid-shaped silicon nanostructures. Until now, atomically smooth surfaces have been extremely challenging to prepare.
“Our ordered array of isosceles silicon pyramids were all the same size and had flat facet planes. We confirmed these findings by low-energy electron diffraction patterns and electron microscopy,” explains lead author of the study Aydar Irmikimov.
An ultrathin — 30 nanometer — layer of iron was deposited onto the silicon to impart unusual magnetic properties. The pyramids’ atomic-level orientation defined the orientation-and thus the properties-of the overlaying iron.
“Epitaxial growth of iron enabled shape anisotropy of the nanofilm. The curve for the magnetization as a function of the magnetic field was rectangular-like shaped but with breaking points which were caused by asymmetric motion of magnetic vortex bound in pyramid apex,” explains Hattori.
The researchers found that the curve had no breaking points in analogous experiments performed on planar iron-coated silicon. Other researchers have theoretically predicted the anomalous curve for pyramid shapes, but the NAIST researchers are the first to have shown it in a real nanostructure.
“Our technology will enable fabrication of a circular magnetic array simply by tuning the shape of the substrate,” says Irmikimov. Integration into advanced technologies such as spintronics — which encode information by the spin, rather than electrical charge, of an electron — will considerably accelerate the functionality of 3D electronics.

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