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Archive for the ‘particle physics’ category: Page 292

Nov 5, 2021

Study reports the ferroelectric switching of spin-to-charge conversion in germanium telluride

Posted by in categories: materials, particle physics

Spintronic devices, a class of architectures that can store or transfer information by leveraging the intrinsic spin of electrons, have been found to be highly promising, both in terms of speed and efficiency. So far, however, the development of these devices has been hindered by the poor compatibility between semiconducting materials and ferromagnetic sources of spin, which underpin their operation.

In fact, while some semiconductors can generate electrical currents from transverse spin currents and vice versa, reliably controlling this spin-charge conversion has so far proved to be highly challenging. In recent years, some material scientists and engineers have thus been investigating the potential of fabricating spintronic devices using ferroelectric Rashba semiconductors, a class of materials with several advantageous properties, such as semiconductivity, large spin-orbit coupling and non-volatility.

A team of researchers at Politecnico di Milano, University Grenoble Alpes and other institutes worldwide have recently demonstrated the non-volatile control of the spin-to-charge conversion in telluride, a known Rashba semiconductor, at room temperature. Their paper, published in Nature Electronics, could have important implications for the future development of spintronic devices.

Nov 4, 2021

A new dimension in magnetism and superconductivity is launched

Posted by in categories: biological, chemistry, nanotechnology, particle physics

An international team of scientists from Austria and Germany has launched a new paradigm in magnetism and superconductivity, putting effects of curvature, topology, and 3D geometry into the spotlight of next-decade research. The results are published in Advanced Materials.

Traditionally, the primary field in which curvature plays a pivotal role is the theory of general relativity. In recent years, however, the impact of curvilinear geometry has entered various disciplines, ranging from solid-state physics to soft-matter physics to chemistry and biology; and giving rise to a plethora of emerging domains, such as curvilinear cell biology, semiconductors, superfluidity, optics, plasmonics and 2D van der Waals materials. In modern magnetism, superconductivity and , extending nanostructures into the has become a major research avenue because of geometry-, curvature-and topology-induced phenomena. This approach provides a means to improve conventional functionalities and to launch novel functionalities by tailoring the curvature and 3D shape.

“In recent years, there have appeared experimental and theoretical works dealing with curvilinear and three-dimensional superconducting and (anti-)ferromagnetic nano-architectures. However, these studies originate from different scientific communities, resulting in the lack of knowledge transfer between such fundamental areas of condensed matter physics as magnetism and superconductivity,” says Oleksandr Dobrovolskiy, head of the SuperSpin Lab at the University of Vienna. “In our group, we lead projects in both these topical areas and it was the aim of our perspective article to build a ‘bridge’ between the magnetism and superconductivity communities, drawing attention to the conceptual aspects of how extension of structures into the third dimension and curvilinear geometry can modify existing and aid launching novel functionalities upon solid-state systems.”

Nov 2, 2021

New Optical Switch Is Up to 1,000 Times Faster Than Silicon Transistors

Posted by in categories: computing, particle physics

It consists of a 35-nanometer-wide film made out of an organic semiconductor sandwiched between two mirrors that create a microcavity, which keeps light trapped inside. When a bright “pump” laser is shone onto the device, photons from its beam couple with the material to create a conglomeration of quasiparticles known as a Bose-Einstein condensate, a collection of particles that behaves like a single atom.

A second weaker laser can be used to switch the condensate between two levels with different numbers of quasiparticles. The level with more particles represents the “on” state of a transistor, while the one with fewer represents the “off” state.

What’s most promising about the new device, described in a paper in Nature, is that it can be switched between its two states a trillion times a second, which is somewhere between 100 and 1,000 times faster than today’s leading commercial transistors. It can also be switched by just a single photon, which means it requires far less energy to drive than a transistor.

Nov 2, 2021

The Jiuzhang 2.0 Photonic Quantum Computer

Posted by in categories: computing, particle physics, quantum physics

The research team lead by professor Pan Jian-Wei has upgraded their photonic quantum computer, demonstrating in a new published study phase-programmable Gaussian boson sampling (GBS) which produces up to 113 photon detection events out of a 144-mode photonic circuit. According to the researchers, the Jiuzhang 2.0 Photonic Quantum Computer (九章二号) is 10 billion times faster than its earlier version. The study “Phase-Programmable Gaussian Boson Sampling Using Stimulated Squeezed Light” was published in the journal Physical Review.

Credit: China Media Group(CMG)/China Central Television (CCTV)

Nov 1, 2021

Hear and Feel BepiColombo Spacecraft’s First Tastes of Mercury Science

Posted by in categories: particle physics, science, space

The magnetic and particle environment around Mercury was sampled by BepiColombo for the first time during the mission’s close flyby of the planet at 199 km on 1–2 October 2,021 while the huge gravitational pull of the planet was felt by its accelerometers.

The magnetic and accelerometer data have been converted into sound files and presented here for the first time. They capture the ‘sound’ of the solar wind as it bombards a planet close to the Sun, the flexing of the spacecraft as it responded to the change in temperature as it flew from the night to dayside of the planet, and even the sound of a science instrument rotating to its ‘park’ position.

Oct 31, 2021

The Large Hadron Collider might have just discovered new physics

Posted by in category: particle physics

Yay 😃


CERN’s gargantuan particle collider could change everything by discovering a new force of nature.

Oct 30, 2021

How much information is in the universe? It’s an unfathomable number

Posted by in category: particle physics

This was described in his 2019 paper, “The mass-energy-information equivalence principle,” which extends Einstein’s theories about the interrelationship of matter and energy to data itself. Consistent with IT, Vopson’s study was based on the principle that information is physical and that all physical systems can register information. He concluded that the mass of an individual bit of information at room temperature (300K) is 3.19 × 10-38 kg (8.598 × 10-38 lbs).

Taking Shannon’s method further, Vopson determined that every elementary particle in the observable Universe has the equivalent of 1.509 bits of encoded information. “It is the first time this approach has been taken in measuring the information content of the universe, and it provides a clear numerical prediction,” he said. “Even if not entirely accurate, the numerical prediction offers a potential avenue toward experimental testing.”

Oct 30, 2021

Is the Great Neutrino Puzzle Pointing to Multiple Missing Particles?

Posted by in categories: particle physics, transportation

In 1,993 deep underground at Los Alamos National Laboratory in New Mexico, a few flashes of light inside a bus-size tank of oil kicked off a detective story that is yet to reach its conclusion.

The Liquid Scintillator Neutrino Detector (LSND) was searching for bursts of radiation created by neutrinos, the lightest and most elusive of all known elementary particles. “Much to our amazement, that’s what we saw,” said Bill Louis, one of the experiment’s leaders.

The problem was that they saw too many. Theorists had postulated that neutrinos might oscillate between types as they fly along — a hypothesis that explained various astronomical observations. LSND had set out to test this idea by aiming a beam of muon neutrinos, one of the three known types, toward the oil tank, and counting the number of electron neutrinos that arrived there. Yet Louis and his team detected far more electron neutrinos arriving in the tank than the simple theory of neutrino oscillations predicted.

Oct 29, 2021

Researchers set ‘ultrabroadband’ record with entangled photons

Posted by in categories: particle physics, quantum physics

Quantum entanglement—or what Albert Einstein once referred to as “spooky action at a distance”— occurs when two quantum particles are connected to each other, even when millions of miles apart. Any observation of one particle affects the other as if they were communicating with each other. When this entanglement involves photons, interesting possibilities emerge, including entangling the photons’ frequencies, the bandwidth of which can be controlled.

Oct 29, 2021

Researchers develop a new way to control and measure energy levels in a diamond crystal

Posted by in categories: computing, engineering, particle physics, quantum physics

Physicists and engineers have long been interested in creating new forms of matter, those not typically found in nature. Such materials might find use someday in, for example, novel computer chips. Beyond applications, they also reveal elusive insights about the fundamental workings of the universe. Recent work at MIT both created and characterized new quantum systems demonstrating dynamical symmetry—particular kinds of behavior that repeat periodically, like a shape folded and reflected through time.

“There are two problems we needed to solve,” says Changhao Li, a graduate student in the lab of Paola Cappellaro, a professor of nuclear science and engineering. Li published the work recently in Physical Review Letters, together with Cappellaro and fellow graduate student Guoqing Wang. “The first problem was that we needed to engineer such a system. And second, how do we characterize it? How do we observe this symmetry?”

Concretely, the quantum system consisted of a diamond crystal about a millimeter across. The crystal contains many imperfections caused by a next to a gap in the lattice—a so-called nitrogen-vacancy center. Just like an electron, each center has a quantum property called a spin, with two discrete . Because the system is a quantum system, the spins can be found not only in one of the levels, but also in a combination of both energy levels, like Schrodinger’s theoretical cat, which can be both alive and dead at the same time.