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The color centers of diamond are the focus of an increasing number of research studies, due to their potential for developing quantum technologies. Some works have particularly explored the use of negatively-charged group-IV diamond defects, which exhibit an efficient spin-photon interface, as the nodes of quantum networks.

Researchers at Ulm University in Germany recently leveraged a Germanium vacancy (GeV) center in diamond to realize a . The resulting quantum memory, presented in a Physical Review Letters paper, was found to exhibit a promising coherence time of more than 20 ms.

“Our research group’s primary focus is the exploration of diamond color centers for quantum applications,” Katharina Senkalla, co-author of the paper, told Phys.org. “The most popular defect of diamond so far has been the nitrogen-vacancy center, but, recently, other color centers have also become a focus of research. These consist of an element from the IV column of the periodic table—Si, Ge, Sn or Pb, and a lattice vacancy (i.e., missing next-neighbor carbon atom).”

Recent research has broken the size limitation of traditional ferroelectric effects, providing experimental evidence and theoretical simulations to confirm that a structure with as few as 5,000 atoms can still exhibit solid-state ferroelectric effects.

The studies, by a joint team from Israel and China, are published in Nature Electronics and Nature Communications under the titles “Ferroelectricity in zero-dimensional” and “0D van der Waals interfacial sliding Ferroelectricity,” respectively.

The ferroelectric effect is a physical phenomenon discovered in the early 20th century by Joseph Valasek, and it provides an important technological route for achieving information storage. Traditional ferroelectric effects are subject to size limitations.

In an experiment akin to stop-motion photography, scientists have isolated the energetic movement of an electron while “freezing” the motion of the much larger atom it orbits in a sample of liquid water.

The findings, reported in the journal Science, provide a new window into the electronic structure of molecules in the liquid phase on a timescale previously unattainable with X-rays. The new technique reveals the immediate electronic response when a target is hit with an X-ray, an important step in understanding the effects of radiation exposure on objects and people.

“The induced by radiation that we want to study are the result of the electronic response of the target that happens on the timescale,” said Linda Young, a senior author of the research and Distinguished Fellow at Argonne National Laboratory.

Auger electron spectroscopy (AES) is an incredibly useful technique for probing material samples—but current assumptions about the process ignore some of the key time-dependent effects it involves. So far, this has resulted in overly-simplified calculations, which have ultimately prevented the technique from reaching its full potential.

In a study published in The European Physical Journal Plus Alberto Noccera at the University of British Columbia, Canada, together with Adrian Feiguin at Northeastern University, United States, developed a which offers a more precise theoretical description of the AES process, while taking its time dependence into account. Their method could help researchers to improve their quality of material analysis across a wide array of fields: including chemistry, , and microelectronics.

In the Auger process, an inner-shell electron is initially kicked out of its atom, often through an impact with an energetic light pulse. Afterward, the vacancy it leaves behind is filled by an outer-shell electron.

The proton, that little positively-charged nugget inside an atom, is fractions of a quadrillionth of a meter smaller than anyone thought, according to new research appearing Nov. 7 in Nature.

In work they hope solves the contentious “proton radius puzzle” that has been roiling some corners of physics in the last decade, a team of scientists including Duke physicist Haiyan Gao have addressed the question of the proton’s radius in a new way and discovered that it is 0.831 femtometers across, which is about 4 percent smaller than the best previous measurement using electrons from accelerators. (Read the paper!)

A single femtometer is 0.000000000000039370 inches imperial, if that helps, or think of it as a millionth part of a billionth part of a meter. And the new radius is just 80 percent of that.

Futuristic advancements in AI and healthcare stole the limelight at the tech extravaganza Consumer Electronics Show (CES) 2024. However, battery technology is the game-changer at the heart of these innovations, enabling greater power efficiency. Importantly, electric vehicles are where this technology is being applied most intensely. Today’s EVs can travel around 700km on a single charge, while researchers are aiming for a 1,000km battery range. Researchers are fervently exploring the use of silicon, known for its high storage capacity, as the anode material in lithium-ion batteries for EVs. However, despite its potential, bringing silicon into practical use remains a puzzle that researchers are still working hard to piece together.

Enter Professor Soojin Park, PhD candidate Minjun Je, and Dr. Hye Bin Son from the Department of Chemistry at Pohang University of Science and Technology (POSTECH). They have cracked the code, developing a pocket-friendly and rock-solid next-generation high-energy-density Li-ion battery system using micro silicon particles and gel polymer electrolytes. This work was published on the online pages of Advanced Science on the 17th of January.

Employing silicon as a battery material presents challenges: It expands by more than three times during charging and then contracts back to its original size while discharging, significantly impacting battery efficiency. Utilizing nano-sized silicon (10-9m) partially addresses the issue, but the sophisticated production process is complex and astronomically expensive, making it a challenging budget proposition. By contrast, micro-sized silicon (10-6m) is superbly practical in terms of cost and energy density. Yet, the expansion issue of the larger silicon particles becomes more pronounced during battery operation, posing limitations for its use as an anode material.

Some of the most bizarre and interesting objects in the Universe are stars. Let’s go on a journey and discover what happens when physics is taken to the most extreme.

Chapters:
00:00 Intro.
03:33 Red dwarfs.
04:53 White dwarfs.
06:39 Black Dwarfs.
08:15 Neutron stars.
13:36 Quark stars.
15:58 Strange stars.
16:35 Electroweak stars.
17:38 Planck stars.

Sources:
All about star birth, life, and death:
https://en.wikipedia.org/wiki/Stellar

About neutron stars:

Consciousness appears to arise naturally as a result of a brain maximizing its information content. So says a group of scientists in Canada and France, which has studied how the electrical activity in people’s brains varies according to individuals’ conscious states. The researchers find that normal waking states are associated with maximum values of what they call a brain’s “entropy”

Statistical mechanics is very good at explaining the macroscopic thermodynamic properties of physical systems in terms of the behaviour of those systems’ microscopic constituent particles. Emboldened by this success, physicists have increasingly been trying to do a similar thing with the brain: namely, using statistical mechanics to model networks of neurons. Key to this has been the study of synchronization – how the electrical activity of one set of neurons can oscillate in phase with that of another set. Synchronization in turn implies that those sets of neurons are physically tied to one another, just as oscillating physical systems, such as pendulums, become synchronized when they are connected together.

The latest work stems from the observation that consciousness, or at least the proper functioning of brains, is associated not with high or even low degrees of synchronicity between neurons but by middling amounts. Jose Luis Perez Velazquez, a biochemist at the University of Toronto, and colleagues hypothesized that what is maximized during consciousness is not connectivity itself but the number of different ways that a certain degree of connectivity can be achieved.

Janus nanosheets bring unprecedented control to preparation of nanoscrolls.

Researchers from Tokyo Metropolitan University have come up with a new way of rolling atomically thin sheets of atoms into “nanoscrolls.” Their unique approach uses transition metal dichalcogenide sheets with a different composition on either side, realizing a tight roll that gives scrolls down to five nanometers in diameter at the center and micrometers in length. Control over the nanostructure in these scrolls promises new developments in catalysis and photovoltaic devices.

Advancements in Nanotechnology.

Atomic clocks are a class of clocks that leverage resonance frequencies of atoms to keep time with high precision. While these clocks have become increasingly advanced and accurate over the years, existing versions might not best utilize the resources they rely on to keep time.

Researchers at the California Institute of Technology recently explored the possibility of using quantum computing techniques to further improve the performance of . Their paper, published in Nature Physics, introduces a new scheme that enables the simultaneous use of multiple atomic clocks to keep time with even greater precision.

“Atomic clocks are decades old, but their performance improves every year,” Adam Shaw, co-author of the paper, told Phys.org.