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Quantum transport through a constriction in nanosheet gate-all-around transistors

In nanoscale transistors, quantum mechanical effects such as tunneling and quantization significantly influence device characteristics. However, large-scale quantum transport simulation remains a challenging field, making it difficult to account for quantum mechanical effects arising from the complex device geometries. Here, based on large-scale quantum transport simulations, we demonstrate that quantum geometrical effects in stacked nanosheet GAAFETs significantly impact carrier injection characteristics. Discontinuities in confinement energy at the constriction—the junction between the bulk source/drain and nanosheet channel—cause substantial carrier backscattering. This degradation becomes more severe as electrons experience higher effective energy barriers, and is further exacerbated at lower scattering rate, lower doping concentrations, and near Schottky barriers where electron depletion regions form. Considering these quantum mechanical bottlenecks, proper device optimization for future technology nodes requires a full quantum-based device structure design at the large-scale level, which enables unique optimization strategies beyond conventional classical prediction.

Kyoung Yeon Kim and colleagues report the importance of quantum geometrical effects that serve as a bottleneck in stacked nanosheet GAAFETs. This highlights that full quantum mechanics-based device design is crucial for realizing ideal carrier injection characteristics in future technology nodes.

Progress and Perspectives in 2D Piezoelectric Materials for Piezotronics and Piezo‐Phototronics

The emergence of two-dimensional (2D) materials has catalyzed significant advancements in the fields of piezotronics and piezo-phototronics, owing to their exceptional mechanical, electronic, and optical properties. This review provides a comprehensive examination of key 2D piezoelectric and piezo-phototronic materials, including transition metal dichalcogenides, hexagonal boron nitride (h-BN), and phosphorene, with an emphasis on their unique advantages and recent research progress. The underlying principles of piezotronics and piezo-phototronics in 2D materials is discussed, focusing on the fundamental mechanisms which enable these phenomena. Additionally, it is analyzed factors affecting piezoelectric and piezo-photoelectric properties, with a particular focus on the intrinsic piezoelectricity of 2D materials and the enhancement of out-of-plane polarization through various modulation techniques and materials engineering approaches. The potential applications of these materials are explored from piezoelectric nanogenerators to piezo-phototronic devices and healthcare. This review addresses future challenges and opportunities, highlighting the transformative impact of 2D materials on the development of next-generation electronic, optoelectronic, and biomedical devices.

This review examines advancements in 2D materials, focusing on their applications in piezotronics and piezo-phototronics. It discusses key materials like TMDs, h-BN, and phosphorene, highlighting their unique mechanical, electronic, and optical properties. The review delves into the mechanisms of piezoelectricity, explores applications such as nanogenerators and biomedical devices, and describes the future and challenges in 3D integration of 2D materials.

Gene linked to skin’s resistance to pressure sheds light on how animals adapted to life on land

One of the most significant moments in the evolutionary journey of life on this planet was the transition from water to land. This huge step required animals to adapt to new challenges, including supporting their body weight and developing new modes of locomotion. These changes put increased pressure on weight-bearing skin, such as paws and soles.

Despite its importance, the by which skin maintains its stability (homeostasis) under this constant pressure have been poorly understood. However, in a paper published in the journal Cell, scientists from China have revealed new insights into how skin adapts to these physical forces.

To better understand what happens, the researchers focused on the Slurp1 gene, which provides instructions for making a protein (SLURP1) found in and other cells that line the surfaces and cavities of the body. It is present in amphibians, reptiles, birds and mammals but not in invertebrates and fish. This suggests that it could’ve emerged alongside terrestrial adaptation.

New 3D topological phase of matter exhibits anomalous symmetry at non-zero temperatures

Some phases of matter cannot be described using the conventional framework of symmetry breaking and exhibit a so-called quantum order. One type of quantum order, known as topological order, is characterized by long-range entanglement between particles across an entire system, a ground state degeneracy that depends on the global shape of the system, and a robustness against local disturbances.

Topological phases of matter primarily occur at zero temperature, as thermal fluctuations tend to destroy them and disrupt their underlying order. In a recent paper published in Physical Review Letters, however, researchers at Nanjing University, Yale University and other institutes reported a new 3D topological phase of matter characterized by an anomalous two-form symmetry that occurs at non-zero temperatures.

“In the last several years, we have made substantial progress in our ability to control —over a range of different platforms: , trapped ions, , photonics, and so on,” Tyler D. Ellison, senior author of the paper, told Phys.org.

Astronomers spot the ‘Eye of Sauron’ in deep space

A stunning new image of a cosmic jet has helped astronomers unlock the mystery behind the unusually bright emission of high-energy gamma rays and neutrinos from a peculiar celestial object. The source is a blazar—a type of active galaxy powered by a supermassive black hole devouring matter at the heart of a galaxy. They have captured what looks like the mythical “Eye of Sauron” in the distant universe and may have just solved a decade-long cosmic puzzle.

Astronomers detect most distant fast radio burst, just 3 billion years after Big Bang

Using the MeerKAT radio telescope, an international team of astronomers have discovered a new fast radio burst, which received designation FRB 20240304B. The measured redshift of FRB 20240304B indicates that it is the most distant fast radio burst known to date. The finding was reported in a research paper published August 3 on the arXiv pre-print server.

Fast radio bursts (FRBs) are intense flashes of radio emission that last only a few milliseconds and showcase the characteristic dispersion sweep of radio pulsars. To date, the physical nature of this mysterious phenomenon remains unknown; however, astronomers consider a variety of explanations ranging from synchrotron maser emission from young magnetars in supernova remnants to cosmic string cusps.

The vast majority of FRBs have been detected at relatively low redshifts of below 0.5. Therefore, their distribution at higher is still poorly studied. That is why astronomers are especially interested in finding new high-redshift FRBs, as they can offer important clues about when the universe was a few billion years old.

Novel protein therapy shows promise as first-ever antidote for carbon monoxide poisoning

University of Maryland School of Medicine (UMSOM) researchers, along with their colleagues, engineered a new molecule that appears promising as an effective antidote for carbon monoxide poisoning with fewer side effects than other molecules currently being tested, according to a new study published in the journal PNAS.

Carbon monoxide poisoning accounts for 50,000 in the U.S. each year and causes about 1,500 deaths. These deaths may occur when released from combustion builds up in an enclosed space, which can result from ventilation failures in indoor natural gas burning equipment, or running gasoline generators or automobiles indoors or in a closed garage. Carbon monoxide poisoning is also associated with most fires from smoke inhalation.

Currently, the only treatments for carbon monoxide poisoning are oxygen-based therapies, which help the body eliminate the toxic gas. However, even with treatment, nearly half of survivors suffer long-term heart and brain damage. This has created an urgent need for faster, more effective therapies.

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