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Study demonstrates atomic layer deposition route to scalable, electronic-grade van der Waals tellurium thin films

A research team, led by Professor Joonki Suh in the Department of Materials Science and Engineering and the Graduate School of Semiconductor Materials and Devices Engineering at UNIST, has made a significant breakthrough in thin film deposition technology. By employing an innovative atomic layer deposition (ALD) process, Professor Seo successfully achieved regular arrangement of tellurium (Te) atoms at low temperatures as low as 50 degrees Celsius.

The ALD method is a cutting-edge thin film process that enables precise stacking of semiconductor materials at the atomic layer level on three-dimensional structures—even at low process temperatures. However, traditional application to next-generation semiconductors requires high processing temperatures above 250 degrees Celsius and additional heat treatment exceeding 450 degrees Celsius.

In this research, the UNIST team applied ALD to monoelemental van der Waals tellurium—a material under extensive investigation for its potential applications in and thermoelectric materials.

Opposites attract? Not in new experiment that finds loophole in fundamental rule of physics

Related: Scientists find ‘ghost particles’ spewing from our Milky Way galaxy in landmark discovery (video)

“Because like-charged objects in a vacuum are expected to repel regardless of whether the sign of the charge they carry is positive or negative, the expectation is that like-charged particles in solution must also monotonically repel,” the researchers wrote in the paper.

To test the assumption, the researchers placed charged silica microparticles (measuring just 0.0002 inch, or 5 micrometers, wide — a fraction of the width of a human hair) inside water or one of two types of alcohol. By tracking the charges with a microscope, the team established that, inside water, the positively charged particles pushed themselves away from each other in accordance with Coulomb’s law.

Mapping the best route for a spacecraft traveling beyond the sun’s sphere of influence

The heliosphere—made of solar wind, solar transients, and the interplanetary magnetic field—acts as our solar system’s personal shield, protecting the planets from galactic cosmic rays. These extremely energetic particles accelerated outwards from events like supernovas and would cause a huge amount of damage if the heliosphere did not mostly absorb them.

Physicists propose new way to search for dark matter: Small-scale solution could be key to solving large-scale mystery

Ever since its discovery, dark matter has remained invisible to scientists despite the launch of multiple ultra-sensitive particle detector experiments around the world over several decades.

Now, physicists at the Department of Energy’s (DOE) SLAC National Accelerator Laboratory are proposing a new way to look for using quantum devices, which might be naturally tuned to detect what researchers call thermalized dark matter.

Most dark matter experiments hunt for galactic dark matter, which rockets into Earth directly from space, but another kind might have been hanging around Earth for years, said SLAC physicist Rebecca Leane, who was an author of the new study.

A method to compute the Rényi entanglement entropy in auxiliary-field quantum Monte Carlo simulations

Entanglement is a widely studied quantum physics phenomenon, in which two particles become linked in such a way that the state of one affects the state of another, irrespective of the distance between them. When studying systems comprised of several strongly interacting particles (i.e., many body systems) in two or more dimensions, numerically predicting the amount of information shared between these particles, a measure known as entanglement entropy (EE), becomes highly challenging.

Magnetic avalanche triggered by quantum effects

Iron screws and other so-called ferromagnetic materials are made up of atoms with electrons that act like little magnets. Normally, the orientations of the magnets are aligned within one region of the material but are not aligned from one region to the next. Think of packs of tourists in Times Square pointing to different billboards all around them. But when a magnetic field is applied, the orientations of the magnets, or spins, in the different regions line up and the material becomes fully magnetized. This would be like the packs of tourists all turning to point at the same sign.

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