Researchers discovered how Floquet Majorana fermions can improve quantum computing by controlling superconducting currents, potentially reducing errors and increasing stability. A new study has revealed significant insights into the behavior of electric current flow in superconductors, which could contribute to advancements in controlled quantum information processing.
Two experiment collaborations, the g2p and EG4 collaborations, combined their complementary data on the proton’s inner structure to improve calculations of a phenomenon in atomic physics known as the hyperfine splitting of hydrogen. An atom of hydrogen is made up of an electron orbiting a proton.
The overall energy level of hydrogen depends on the spin orientation of the proton and electron. If one is up and one is down, the atom will be in its lowest energy state. But if the spins of these particles are the same, the energy level of the atom will increase by a small, or hyperfine, amount. These spin-born differences in the energy level of an atom are known as hyperfine splitting.
While it’s commonplace for many scientists to collaborate on nuclear physics experiments at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility, it’s rarer for the lab’s individual experiments to collaborate with each other. But that’s exactly what g2p in Jefferson Lab’s Experimental Hall A and EG4 in Experimental Hall B did.
The Axion Longitudinal Plasma Haloscope (ALPHA) experiment reached a milestone on February 24 with the successful installation of a Bluefors helium dilution fridge at the site of the experiment in Wright Lab.
ALPHA will extend the search for a hypothetical dark matter candidate—a very low-mass particle called the axion—to a higher mass range than has been searched for previously.
Michael Jewell, associate research scientist in physics and a member of Yale’s Wright Lab is the ALPHA project technical coordinator. Jewell explained, “In order for ALPHA to achieve its physics goal, we need to limit any potential noise source. For us, the biggest source of noise is thermal noise from the experiment. So we operate the whole experiment in the coldest commercially available systems, which are helium dilution fridges that are able to cool down to ~10 millikelvin (mK).”
Deep within certain magnetic molecules, atoms arrange their spins in a spiral pattern, forming structures called chiral helimagnets. These helical spin patterns have intrigued researchers for years due to their potential for powering next-generation electronics. But decoding their properties has remained a mystery—until now.
Researchers at the University of California San Diego have developed a new computational approach to accurately model and predict these complex spin structures using quantum mechanics calculations. Their work was published on Feb. 19 in Advanced Functional Materials.
“The helical spin structures in two-dimensional layered materials have been experimentally observed for over 40 years. It has been a longstanding challenge to predict them with precision,” said Kesong Yang, professor in the Aiiso Yufeng Li Family Department of Chemical and Nano Engineering at the UC San Diego Jacobs School of Engineering and senior author of the study. “The helical period in the layered compound extends up to 48 nanometers, making it extremely difficult to accurately calculate all the electron and spin interactions at this scale.”
In the annals of scientific inquiry, few endeavors have been as audacious as the attempt to bridge the chasm between the tangible and the intangible, the empirical and the experiential. The declassification of the 1983 U.S. Army Intelligence report, “Analysis and Assessment of The Gateway Process,” offers a compelling case study in this regard. Authored by Lieutenant Colonel Wayne M. McDonnell, the report delves into altered states of consciousness, suggesting that human consciousness may transcend the physical plane, potentially supporting concepts akin to reincarnation. This proposition invites us to explore the intersection of infodynamics — the study of information dynamics within physical systems — and phenomena traditionally deemed spiritual, under the premise that all such phenomena are rooted in the natural order.
At the heart of this exploration lies the principle that information, much like energy, is conserved within the universe. This concept is reminiscent of the first law of thermodynamics, which asserts that energy cannot be created or destroyed, only transformed. In the realm of information theory, this translates to the idea that information persists, undergoing transformations but never facing annihilation. This perspective aligns with the notion that consciousness, as a form of information, may continue beyond the cessation of its current physical embodiment.
Quantum mechanics further enriches this discourse. The phenomenon of quantum entanglement, wherein particles become interconnected in such a way that the state of one instantaneously influences the state of another, regardless of the spatial separation, challenges our classical understanding of locality and separability. This non-locality suggests a deeply interconnected fabric of reality, where information is not confined to a singular point in space or time. Such a framework provides a plausible basis for understanding how consciousness, as an informational construct, could transcend individual physical forms, offering a naturalistic foundation for phenomena like reincarnation.
When molecules collide with surfaces, they exchange energy with the surface atoms. This complex process is influenced by quantum interference, where different pathways overlap, creating patterns where some paths enhance each other while others cancel out. This affects how molecules exchange energy and react with surfaces.
Observing quantum interference in collisions with heavier molecules like methane (CH4) was challenging due to the many possible pathways. Scientists wondered if quantum effects would disappear, making classical physics enough to describe these processes.
In classical electromagnetism, electric and magnetic fields are the fundamental entities responsible for all physical effects. There is a compact formulation of electromagnetism that expresses the fields in terms of another quantity known as the electromagnetic potential, which can have a value everywhere in space. The fields are easily derived theoretically from the potential, but the potential itself was taken to be purely a mathematical device, with no physical meaning.
In quantum mechanics, shifts in the electromagnetic potential alter the description of a charged particle only by shifting its phase—that is, by advancing or retarding the crests and troughs in its quantum wave function. In general, however, such a phase change does not lead to any difference in the measurable properties of a particle.
But in 1959 Yakir Aharonov and David Bohm of the University of Bristol, UK, devised a thought experiment that linked the potential to a measurable result. In their scenario, a beam of electrons is split, with the two halves made to travel around opposite sides of a cylindrical electromagnet, or solenoid. The magnetic field is concentrated inside the solenoid and can be made arbitrarily weak outside by making the cylinder extremely narrow. So Aharonov and Bohm argued that the two electron paths can travel through an essentially field-free region that surrounds the concentrated field within the electromagnet.
For decades, scientists have relied on electrodes and dyes to track the electrical activity of living cells. Now, engineers at the University of California San Diego have discovered that quantum materials just a single atom thick can do the job—using only light.
A new study, published in Nature Photonics, shows that these ultra-thin semiconductors, which trap electrons in two dimensions, can be used to sense the biological electrical activity of living cells with high speed and resolution.
Scientists have continually been seeking better ways to track the electrical activity of the body’s most excitable cells, such as neurons, heart muscle fibers and pancreatic cells. These tiny electrical pulses orchestrate everything from thought to movement to metabolism, but capturing them in real time and at large scales has remained a challenge.
Light was long considered to be a wave, exhibiting the phenomenon of interference in which ripples like those in water waves are generated under specific interactions. Light also bends around corners, resulting in fringing effects, which is termed diffraction. The energy of light is associated with its intensity and is proportional to the square of the amplitude of the electric field, but in the photoelectric effect, the energy of emitted electrons is found to be proportional to the frequency of radiation.
This observation was first made by Philipp Lenard, who did initial work on the photoelectric effect. In order to explain this, in 1905, Einstein suggested in Annalen der Physik that light comprises quantized packets of energy, which came to be called photons. It led to the theory of the dual nature of light, according to which light can behave like a wave or a particle depending on its interactions, paving the way for the birth of quantum mechanics.
Although Einstein’s work on photons found broader acceptance, eventually leading to his Nobel Prize in Physics, Einstein was not fully convinced. He wrote in a 1951 letter, “All the 50 years of conscious brooding have brought me no closer to the answer to the question: What are light quanta?”
A team of physicists at the SLAC National Accelerator Laboratory, in Menlo Park, California, generated the highest-current, highest-peak-power electron beams ever produced. The team has published their paper in Physical Review Letters.
For many years, scientists have been finding new uses for high-powered laser light, from splitting atoms to mimicking conditions inside other planets. For this new study, the research team upped the power of electron beams, giving them some of the same capabilities.
The idea behind the newer, more powerful beams was pretty simple, the team acknowledges; it was figuring out how to make it happen that was difficult. The basic idea is to pack as much charge as possible into the shortest amount of time. In their work, they generated 100 kiloamps of current for just one quadrillionth of a second.
