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The images shed light on how electrons form superconducting pairs that glide through materials without friction.

When your laptop or smartphone heats up, it’s due to energy that’s lost in translation. The same goes for power lines that transmit electricity between cities. In fact, around 10 percent of the generated energy is lost in the transmission of electricity. That’s because the electrons that carry electric charge do so as free agents, bumping and grazing against other electrons as they move collectively through power cords and transmission lines. All this jostling generates friction, and, ultimately, heat.

But when electrons pair up, they can rise above the fray and glide through a material without friction. This “superconducting” behavior occurs in a range of materials, though at ultracold temperatures. If these materials can be made to superconduct closer to room temperature, they could pave the way for zero-loss devices, such as heat-free laptops and phones, and ultra-efficient power lines. But first, scientists will have to understand how electrons pair up in the first place.

“A phonon represents the collective motion of an astronomical number of atoms,” Cleland says. “And they all have to work together in order to obey quantum mechanics. There was this question in the back of my mind, will this really work? We tried it, and it’s kind of amazing, but it really does work.”

Splitting a phonon

The team created single phonons as propagating wavepackets on the surface of a lithium niobate chip. The phonons were created and detected using two superconducting qubits, which were located on a separate chip, and coupled to the lithium niobate chip through the air. The two superconducting qubits were located either of the chip, with a two-millimetre-long channel between them hosting the travelling phonons.

The quantum nature of interactions between elementary particles allows drawing non-trivial conclusions even from processes as simple as elastic scattering. The ATLAS experiment at the LHC accelerator reports the measurement of fundamental properties of strong interactions between protons at ultra-high energies.

The physics of billiard ball collisions is taught from early school years. In a good approximation, these collisions are elastic, where both momentum and energy are conserved. The scattering angle depends on how central the collision was (this is often quantified by the impact parameter value—the distance between the centers of the balls in a plane perpendicular to the motion). In the case of a small impact parameter, which corresponds to a highly central collision, the scattering angles are large. As the impact parameter increases, the scattering angle decreases.

In particle physics, we also deal with elastic collisions, when two particles collide, maintaining their identities, and scatter a certain angle to their original direction of motion. Here, we also have a relationship between the collision parameter and the scattering angle. By measuring the scattering angles, we gain information about the spatial structure of the colliding particles and the properties of their interactions.

An international team of physicists has succeeded in measuring a property of the electron known as topological spin winding for the first time. The team obtained this result by studying the behaviour of electrons in so-called kagome metals, which are materials that have unique quantum properties related to their physical shape, or topology. The work could advance our understanding of the physics of superconductors and other systems that contain strongly correlated electrons.

Kagome metals are named after a traditional Japanese basket-weaving technique that produces a lattice of interlaced, symmetrical triangles with shared corners. When the atoms of a metal or other conductor are arranged in this kagome pattern, their electrons behave in unusual ways. For example, the wavefunctions of the electrons can interfere destructively, resulting in highly localized electronic states in which the particles interact strongly with each other. These strong interactions lead to a range of quantum phenomena, including magnetic ordering of unpaired electrons spins that can produce, for example, ferro-or antiferromagnetic phases, superconducting structures, quantum spin liquids and abnormal topological phases. All these phases have applications in advanced nanoelectronics and spintronics technologies.

In the new work, researchers led by Domenico Di Sante of the University of Bologna in Italy studied the spin and electronic structure of XV₆Sn₆, where X is a rare-earth element. These recently-discovered kagome metals contain a Dirac electronic band and a nearly flat electronic band. At the point at which these bands meet, an effect called spin-orbit coupling creates a narrow gap between the bands. This spin-orbit coupling also creates special type of electronic ground state at the material’s surface.

It seems quantum mechanics and thermodynamics cannot be true simultaneously. In a new publication, University of Twente researchers use photons in an optical chip to demonstrate how both theories can be true at the same time.

In quantum mechanics, time can be reversed and information is always preserved. That is, one can always find back the previous state of particles. It was long unknown how this could be true at the same time as thermodynamics. There, time has a direction and information can also be lost. “Just think of two photographs that you put in the sun for too long, after a while you can no longer distinguish them,” explains author Jelmer Renema.

There was already a theoretical solution to this quantum puzzle and even an experiment with atoms, but now the University of Twente (UT) researchers have also demonstrated it with photons. “Photons have the advantage that it is quite easy to reverse time with them,” explains Renema. In the experiment, the researchers used an optical chip with channels through which the photons could pass. At first, they could determine exactly how many photons there were in each channel, but after that, the photons shuffled positions.

Inside a lab, scientists marvel at a strange state that forms when they cool down atoms to nearly absolute zero. Meanwhile, just outside their window, trees are absorbing sunlight and converting it into new leaves. These two scenarios may seem entirely unrelated, but a recent study from the University of Chicago proposes that these processes are not as distinct as they might appear on the surface.

Published in the journal PRX Energy, the study established connections at the atomic level between the process of photosynthesis and exciton condensates, —a strange state of physics that allows energy to flow frictionlessly through a material. According to the authors, this discovery is not only fascinating from a scientific perspective, but it may also offer new perspectives for electronics design.

Phase change memory is a type of nonvolatile memory that harnesses a phase change material’s (PCM) ability to shift from an amorphous state, i.e., where atoms are disorganized, to a crystalline state, i.e., where atoms are tightly packed close together. This change produces a reversible electrical property which can be engineered to store and retrieve data.

While this field is in its infancy, phase change memory could potentially revolutionize data storage because of its high storage density, and faster read and write capabilities. But still, the complex switching mechanism and intricate fabrication methods associated with these materials have posed challenges for mass production.

In recent years, two-dimensional (2D) Van Der Waals (vdW) transition metal di-chalcogenides have emerged as a promising PCM for usage in phase change memory.

There’s a new way to harness the power of the sun and it may just revolutionize how we approach solar energy. The development is called quantum dots and it consists of tiny semiconductor particles only a few nanometers in size.

This is according to a report by Fagen Wasanni published on Saturday.

“Quantum dots have unique properties that make them ideal for use in solar cells. Their small size allows them to absorb light from a wide range of wavelengths, including those that traditional solar cells cannot capture. This means that quantum dot-based solar cells can potentially convert more sunlight into electricity, significantly increasing their efficiency,” states the report.

Scientists have created an innovative model membrane electrode with hollow giant carbon nanotubes and a wide range of nanopore dimensions. The invention aids in understanding electrochemical behaviors and could significantly advance our knowledge of porous carbon materials in electrochemical systems.

Researchers at Tohoku University and Tsinghua University have introduced a next-generation model membrane electrode that promises to revolutionize fundamental electrochemical research. This innovative electrode, fabricated through a meticulous process, showcases an ordered array of hollow giant carbon nanotubes (gCNTs) within a nanoporous membrane, unlocking new possibilities for energy storage and electrochemical studies.

The key breakthrough lies in the construction of this novel electrode. The researchers developed a uniform carbon coating technique on anodic aluminum oxide (AAO) formed on an aluminum substrate, with the barrier layer eliminated. The resulting conformally carbon-coated layer exhibits vertically aligned gCNTs with nanopores ranging from 10 to 200 nm in diameter and 2 μm to 90 μm in length, covering small electrolyte molecules to bio-related large matters such as enzymes and exosomes. Unlike traditional composite electrodes, this self-standing model electrode eliminates inter-particle contact, ensuring minimal contact resistance — something essential for interpreting the corresponding electrochemical behaviors.