A river can carry a contaminant far beyond the point where it enters the water, but predicting exactly how quickly that material will travel is not always straightforward. In 2010, scientists with the U.S.
Category: materials – Page 5
In 2019, UT Austin and Lockheed Martin developed a hydrogel system producing 12 times more water than commercial solar stills. 7 years later, its 3.6 L/h/m² rate remains a striking benchmark in solar purification
Seven years after the original 2019 report, the reported 3.6 liters per hour per square meter remains an interesting benchmark for understanding the potential of solar purification research. The lasting value of the work is not simply the numerical comparison with commercial solar stills but the broader principle behind it: materials can be engineered to make renewable-energy technologies more productive.
Hyperdoped silicon photodiode advances short-wave infrared detection at room temperature
Detecting short-wave infrared (SWIR) light, a region of the electromagnetic spectrum just beyond the light visible to the human eye, could be advantageous for many real-world applications. For instance, it could enable more advanced systems for capturing images at night, as well as sophisticated medical imaging, environmental monitoring and industrial inspection technologies.
Despite their potential, most SWIR detection devices developed so far are based on expensive semiconducting materials that are often difficult to integrate with existing electronic hardware. This is because silicon, the most widely used semiconductor in the electronics industry, cannot absorb SWIR photons due to its wide band gap.
Researchers at Complutense University of Madrid have developed a silicon photodiode that can efficiently absorb SWIR light and is compatible with current electronics manufacturing processes. The new device, introduced in a paper published in Physical Review Letters, is based on silicon doped with a high concentration of tellurium (Te) atoms.
Tiny atomic changes could lead to smarter wireless technology
Researchers at Queen Mary University of London have shown that making extremely small changes to the structure of a material can dramatically improve its ability to respond to electrical signals. Published recently in Science Advances, the breakthrough could help create a new generation of wireless devices that can change frequency on demand, making communication systems more flexible and energy efficient.
The team focused on a ceramic material called strontium tantalate. By replacing a small number of atoms with slightly smaller calcium atoms, they created tiny distortions in the material’s structure. Although these changes occur at the atomic scale, they have a major effect on how the material behaves.
Narrow ultrasonic beam enables stable 3D levitation six times farther than before
Scientists have developed a new acoustic levitation technique using an ultrasonic beam capable of levitating and moving small objects in midair over distances of up to 40 cm (16 inches), six times farther than previously achieved using conventional methods. The study, carried out by a research team from the University of Tsukuba in Japan and the University of Bristol, was published in the journal Physical Review Letters.
Acoustic levitation is a technique that uses sound waves to suspend objects in midair without physical contact—meaning it has the potential to be beneficial for handling fragile materials, contamination-sensitive samples and hazardous substances.
Conventional acoustic levitation systems rely on sound waves generated within an enclosed space, but the new technique is the first time a single-sided design has demonstrated stable acoustic levitation in three dimensions.
High magnetic fields revive superconductivity in nickelates
Scientists from the National University of Singapore (NUS), in collaboration with Los Alamos National Laboratory in the United States, have uncovered that a class of nickel-based materials known as samarium (Sm)-based infinite-layer nickelates can regain their superconducting ability under strong magnetic fields. This behavior could open a promising pathway toward superconducting technologies that can operate under extreme magnetic conditions.
Superconductivity, the ability of certain materials to conduct electricity without resistance, is typically destroyed by strong magnetic fields. However, a research team led by Professor Ariando from the Department of Physics at NUS, working with scientists from Los Alamos National Laboratory, has shown that Sm-based infinite-layer nickelates defy this expectation.
In these nickelates, superconductivity is first suppressed at low magnetic fields of a few tesla, only to reappear as the field increases, persisting beyond 60 tesla (hundreds of thousands of times stronger than Earth’s magnetic field). This unusual behavior, known as reentrant superconductivity, has previously been observed only in materials with very low transition temperatures, limiting their practical relevance.
Researchers Solve Two Major Problems Holding Back SiC Electronics
A new bottom gate design takes advantage of the intrinsic properties of SiC.
For more than 20 years, silicon carbide – SiC – has been viewed as a promising material for electronics that must function in extreme environments. Yet despite years of research, that promise has rarely translated into practical devices. Researchers at Kyoto University are now trying to move the field beyond that barrier.
“We believe the lack of development is because the research community has been trying to apply silicon-era thinking to a fundamentally different material,” says first author Mitsuaki Kaneko.
The superconducting gap of an ultrathin nickelate defies expectations
Superconductors are materials that carry electrical current with zero resistance below a specific critical temperature. In conventional superconductors, the transition to superconductivity generally occurs at very low temperatures.
Some unconventional superconductors, however, enter their superconducting phase at comparatively higher critical temperatures. This could be advantageous for practical applications, as superconductivity at higher temperatures could reduce the need for complex and expensive cooling systems. However, these materials generally still require substantial cooling.
Researchers at Nanjing University, the University of Science and Technology of China, the Hong Kong Polytechnic University and other institutes in China recently investigated the electronic processes underpinning superconductivity in La₃Ni₂O₇, a nickelate that has exhibited superconductivity at temperatures of up to around 80 K (−193°C, −316°F) under very high pressure.
Physicists Discover Time Crystals Can Communicate Across a Semiconductor
Separate time crystals inside a semiconductor can “find” each other across surprising distances and lock into the same rhythm.
Researchers at TU Dortmund University demonstrated the effect using a semiconductor system in which electron and nuclear spins form continuous time crystals. Their latest experiments, published in Nature Communications, reveal that spatially separated oscillators can lock to the same frequency even when they begin with different rhythms.
The finding builds on the team’s earlier demonstration of an unusually robust continuous time crystal in a semiconductor. That system produced persistent electron-nuclear spin oscillations with coherence lasting for hours, giving the researchers a stable platform for exploring what happens when several time crystals occupy the same material.