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To operate safely and reliably in outdoor environments, electronic devices should be resistant to a wide variety of external factors, including radiation. In fact, high-energy radiation can damage several components of field-effect transistors (FETs) commonly used to make electronics, including their superconducting channel, gate oxide and the insulating materials surrounding it (e.g., isolation or substrate oxides).

For several years, research teams worldwide have thus been trying to devise strategies that could make transistors more resistant to radiation. So far, however, this has proved to be highly challenging, and only a few of the techniques proposed in the past have achieved promising results.

Researchers at Peking University, the Chinese Academy of Sciences and Shanghai Tech University have recently fabricated a radiation-hardened and repairable integrated circuit (IC) based on carbon nanotube transistors with ion gel gates. This IC, first presented in a paper pre-published in Nature Electronics, could be used to build new electronic devices that are more resistant to high-energy radiation.

One of the key challenges in developing effective, targeted cancer treatments is the heterogeneity of the cancer cells themselves. This variation makes it difficult for the immune system to recognize, respond to and actively fight against tumors. Now, however, new advances in nanotechnology are making it possible to deliver targeted, personalized “vaccines” to treat cancer.

A new study, published on October 2, 2020 in Science Advances, demonstrates the use of charged nanoscale metal-organic frameworks for generating free radicals using X-rays within tumor tissue to kill cancer cells directly. Furthermore, the same frameworks can be used for delivering immune signaling molecules known as PAMPs to activate the immune response against tumor cells. By combining these two approaches into one easily administered “vaccine,” this new technology may provide the key to better local and systemic treatment of difficult-to-treat cancers.

In a collaboration between the Lin Group in the University of Chicago Department of Chemistry and the Weichselbaum Lab at University of Chicago Medicine, the research team combined expertise from inorganic chemistry and cancer biology to tackle the challenging problem of properly targeting and activating an innate immune response against cancer. This work leveraged the unique properties of nanoscale metal-organic frameworks, or nMOFs —nanoscale structures built of repeating units in a lattice formation that are capable of infiltrating tumors.

Technion researchers have developed accurate radiation sources that are expected to lead to breakthroughs in medical imaging and other areas. They have developed precise radiation sources that may replace the expensive and cumbersome facilities currently used for such tasks. The suggested apparatus produces controlled radiation with a narrow spectrum that can be tuned with high resolution, at a relatively low energy investment. The findings are likely to lead to breakthroughs in a variety of fields, including the analysis of chemicals and biological materials, medical imaging, X-ray equipment for security screening, and other uses of accurate X-ray sources.

Published in the journal Nature Photonics, the study was led by Professor Ido Kaminer and his master’s student Michael Shentcis as part of a collaboration with several research institutes at the Technion: the Andrew and Erna Viterbi Faculty of Electrical Engineering, the Solid State Institute, the Russell Berrie Nanotechnology Institute (RBNI), and the Helen Diller Center for Quantum Science, Matter and Engineering.

The researchers’ paper shows an experimental observation that provides the first proof-of-concept for theoretical models developed over the last decade in a series of constitutive articles. The first article on the subject also appeared in Nature Photonics. Written by Prof. Kaminer during his postdoc at MIT, under the supervision of Prof. Marin Soljacic and Prof. John Joannopoulos, that paper presented theoretically how two-dimensional materials can create X-rays. According to Prof. Kaminer, “that article marked the beginning of a journey towards radiation sources based on the unique physics of two-dimensional materials and their various combinations—heterostructures. We have built on the theoretical breakthrough from that article to develop a series of follow-up articles, and now, we are excited to announce the first experimental observation on the creation of X-ray radiation from such materials, while precisely controlling the radiation parameters.”

Based on focused electron beam-induced processing (FEBID) techniques, the work could allow production of 2-D/3D complex nanostructures and functional nanodevices useful in quantum communications, sensing, and other applications. For oxygen-containing materials such as graphene oxide, etching can be done without introducing outside materials, using oxygen from the substrate.

“By timing and tuning the energy of the electron beam, we can activate interaction of the beam with oxygen in the graphene oxide to do etching, or interaction with hydrocarbons on the surface to create carbon deposition,” said Andrei Fedorov, professor and Rae S. and Frank H. Neely Chair in the George W. Woodruff School of Mechanical Engineering at the Georgia Institute of Technology. “With atomic-scale control, we can produce complicated patterns using direct write-remove processes. Quantum systems require precise control on an atomic scale, and this could enable a host of potential applications.”

Scientists typically prefer to work with ordered systems. However, a diverse team of physicists and biophysicists from the University of Groningen found that individual light-harvesting nanotubes with disordered molecular structures still transport light energy in the same way. By combining spectroscopy, molecular dynamics simulations and theoretical physics, they discovered how disorder at the molecular level is effectively averaged out at the microscopic scale. The results were published on 28 September in the Journal of the American Chemical Society.

The double-walled light-harvesting nanotubes self-assemble from molecular building blocks. They are inspired by the multi-walled tubular antenna network of photosynthetic bacteria found in nature. The nanotubes absorb and transport light energy, although it was not entirely clear how. “The nanotubes have similar sizes but they are all different at the molecular level with the molecules arranged in a disordered way,” explains Maxim Pshenichnikov, Professor of Ultrafast Spectroscopy at the University of Groningen.

Physicists at Chalmers, together with colleagues in Russia and Poland, have managed to achieve ultrastrong coupling between light and matter at room temperature. The discovery is of importance for fundamental research and might pave the way for advances within, for example, light sources, nanomachinery, and quantum technology.

A set of two coupled oscillators is one of the most fundamental and abundant systems in physics. It is a very general toy model that describes a plethora of systems ranging from guitar strings, acoustic resonators, and the physics of children’s swings, to molecules and chemical reactions, from gravitationally bound systems to quantum cavity electrodynamics. The degree of coupling between the two oscillators is an important parameter that mostly determines the behavior of the coupled system. However, the question is rarely asked about the upper limit by which two pendula can couple to each other – and what consequences such coupling can have.

The newly presented results, published in Nature Communications, offer a glimpse into the domain of the so-called ultrastrong coupling, wherein the coupling strength becomes comparable to the resonant frequency of the oscillators. The coupling in this work is realized through interaction between light and electrons in a tiny system consisting of two gold mirrors separated by a small distance and plasmonic gold nanorods. On a surface that is a hundred times smaller than the end of a human hair, the researchers have shown that it is possible to create controllable ultrastrong interaction between light and matter at ambient conditions – that is, at room temperature and atmospheric pressure.

Researchers took a silica nanoparticle designated as ‘Generally Recognized As Safe’ by the US Food and Drug Administration and coated it with L-phenylalanine, and found that in lab tests with mice it killed cancer cells effectively and very specifically, by causing them to self-destruct.

Cancer cells are killed in lab experiments and tumor growth reduced in mice, using a new approach that turns a nanoparticle into a ‘Trojan horse’ that causes cancer cells to self-destruct, a research team at the Nanyang Technological University, Singapore (NTU Singapore) has found.

The researchers created their ‘Trojan horse’ nanoparticle by coating it with a specific amino acid — L-phenylalanine — that cancer cells rely on, along with other similar amino acids, to survive and grow. L-phenylalanine is known as an ‘essential’ amino acid as it cannot be made by the body and must be absorbed from food, typically from meat and dairy products.

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Nanoscale vortices known as skyrmions can be created in many magnetic materials. For the first time, researchers at PSI have managed to create and identify antiferromagnetic skyrmions with a unique property: critical elements inside them are arranged in opposing directions. Scientists have succeeded in visualizing this phenomenon using neutron scattering. Their discovery is a major step towards developing potential new applications, such as more efficient computers. The results of the research are published today in the journal Nature.

Whether a material is magnetic depends on the spins of its atoms. The best way to think of spins is as minute bar magnets. In a crystal structure where the atoms have fixed positions in a lattice, these spins can be arranged in criss-cross fashion or aligned all in parallel like the spears of a Roman legion, depending on the individual material and its state.

Under certain conditions it is possible to generate tiny vortices within the corps of spins. These are known as skyrmions. Scientists are particularly interested in skyrmions as a key component in future technologies, such as more efficient data storage and transfer. For example, they could be used as memory bits: a skyrmion could represent the digital one, and its absence a digital zero. As skyrmions are significantly smaller than the bits used in conventional storage media, data density is much higher and potentially also more energy efficient, while read and write operations would be faster as well. Skyrmions could therefore be useful both in classical data processing and in cutting-edge quantum computing.

Physicists at Chalmers University of Technology in Sweden, together with colleagues in Russia and Poland, have managed to achieve ultra-strong coupling between light and matter at room temperature. The discovery is of importance for fundamental research and might pave the way for advances in light sources, nanomachinery and quantum technology.

A set of two coupled oscillators is one of the most fundamental and widely used systems in physics. It is a very general toy model that describes a plethora of systems including guitar strings, acoustic resonators, the physics of children’s swings, molecules and chemical reactions, gravitationally bound systems, and quantum cavity electrodynamics.

The degree of coupling between the two oscillators is an important parameter that mostly determines the behavior of the coupled system. However, not much is known about the upper limit by which two pendula can couple to each other—and what consequences such coupling can have.