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Low-power MoS₂-based microwave transmitter could advance communications

To further advance wireless communication systems, electronics engineers have been trying to develop new electronic circuits that operate in the microwave frequency range (1–300 GHz), while also losing little energy while transmitting signals. Ideally, these circuits should also be more compact than existing solutions, as this would help to reduce the overall size of communication systems.

Most of the microwaves integrated in current communication systems are made of bulk materials, such as silicon or gallium arsenide. While these circuits have achieved good results so far, both their size and have proved to be difficult to reduce further.

Two-dimensional (2D) semiconducting materials, which are made up of a single atomic layer, could overcome the limitations of bulk materials, as they are both thinner and exhibit advantageous electrical properties. Among these materials, (MoS₂), has been found to be particularly promising for the development of circuits and other components for communication systems.

A new attempt to explain the accelerated expansion of the universe

Why is the universe expanding at an ever-increasing rate? This is one of the most exciting yet unresolved questions in modern physics. Because it cannot be fully answered using our current physical worldview, researchers assume the existence of a mysterious “dark energy.” However, its origin remains unclear to this day.

An international research team from the Center for Applied Space Technology and Microgravity (ZARM) at the University of Bremen and the Transylvanian University of Brașov in Romania has come to the conclusion that the expansion of the universe can be explained—at least in part—without dark energy.

In physics, the evolution of the universe has so far been described by the and the so-called Friedmann equations. However, in order to explain the observed expansion of the universe on this basis, an additional “dark energy term” must be manually added to the equations.

Rigorous approach quantifies and verifies almost all quantum states

Quantum information systems, systems that process, store or transmit information leveraging quantum mechanical effects, could, in principle, outperform classical systems in some optimization, computational, sensing, and learning tasks. An important aspect of quantum information science is the reliable quantification of quantum states in a system, to verify that they match desired (i.e., target) states.

Atom-scale stencil patterns help nanoparticles take new shapes and learn new tricks

Inspired by an artist’s stencils, researchers have developed atomic-level precision patterning on nanoparticle surfaces, allowing them to “paint” gold nanoparticles with polymers to give them an array of new shapes and functions.

The “patchy nanoparticles” developed by University of Illinois Urbana-Champaign researchers and collaborators at the University of Michigan and Penn State University can be made in large batches, used for a variety of electronic, optical or biomedical applications, or used as building blocks for new complex materials and metamaterials.

Led by Qian Chen, an Illinois professor of materials science and engineering, the researchers report their findings in the journal Nature.

Researchers pioneer fluid-based laser scanning for brain imaging

When Darwin Quiroz first started working with optics as an undergraduate, he was developing atomic magnetometers. That experience sparked a growing curiosity about how light interacts with matter, an interest that has now led him to a new technique in optical imaging.

Quiroz, a Ph.D. student in the Department of Electrical, Computer and Energy Engineering at the University of Colorado Boulder, is co-first author of a new study that demonstrates how a fluid-based known as an electrowetting prism can be used to steer lasers at high speeds for advanced imaging applications.

The work, published in Optics Express, conducted along with mechanical engineering Ph.D. graduate Eduardo Miscles and Mo Zohrabi, senior research associate, opens the door to new technologies in microscopy, LiDAR, optical communications and even brain imaging.

Why some quantum materials stall while others scale

People tend to think of quantum materials—whose properties arise from quantum mechanical effects—as exotic curiosities. But some quantum materials have become a ubiquitous part of our computer hard drives, TV screens, and medical devices. Still, the vast majority of quantum materials never accomplish much outside of the lab.

What makes certain commercial successes and others commercially irrelevant? If researchers knew, they could direct their efforts toward more promising materials—a big deal since they may spend years studying a single material.

Now, MIT researchers have developed a system for evaluating the scale-up potential of quantum materials. Their framework combines a material’s quantum behavior with its cost, supply chain resilience, environmental footprint, and other factors.

Our team of physicists inadvertently generated the shortest X-ray pulses ever observed

X-ray beams aren’t used just by doctors to see inside your body and tell whether you have a broken bone. More powerful beams made up of very short flashes of X-rays can help scientists peer into the structure of individual atoms and molecules and differentiate types of elements.

But getting an X-ray laser beam that delivers super short flashes to capture the fastest processes in nature isn’t easy—it’s a whole science in itself.

Radio waves, microwaves, the visible light you can see, and X-rays are all exactly the same phenomenon: electromagnetic waves of energy moving through space. What differentiates them is their wavelength. Waves in the X-ray range have short wavelengths, while radio waves and microwaves are much longer. Different wavelengths of light are useful for different things—X-rays help doctors take snapshots of your body, while microwaves can heat up your lunch.

DNA signaling cascades offer a better way to monitor drug therapy at home

Chemists at Université de Montréal have developed “signaling cascades” made with DNA molecules to report and quantify the concentration of various molecules in a drop of blood, all within five minutes.

Their findings, validated by experiments on mice, are published in the Journal of the American Chemical Society, and may aid efforts to build point-of-care devices for monitoring and optimizing the treatment of various diseases.

This result was achieved by a research group led by UdeM chemistry professor Alexis Vallée-Bélisle.

Generation of harmful slow electrons in water is a race between intermolecular energy decay and proton transfer

When high-energy radiation interacts with water in living organisms, it generates particles and slow-moving electrons that can subsequently damage critical molecules like DNA. Now, Professor Petr Slavíček and his bachelor’s student Jakub Dubský from UCT Prague (University of Chemistry and Technology, Prague) have described in detail one of the key mechanisms for the creation of these slow electrons in water, a process known as Intermolecular Coulombic Decay (ICD). Their powerful mathematical model successfully explains all the data from complex laser experiments conducted at ETH Zurich (Hans-Jakob Woerner team).

The work, which deepens the fundamental understanding of radiation chemistry, has been published in the journal Nature Communications.

A detailed knowledge of the processes in , combined with advances in research technologies using high-energy radiation, is transforming the field of radiation chemistry. In the future, these insights could lead to significant changes in various fields, including medicine, particularly in developing more sensitive and controllable applications for devices based on ionizing radiation.

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