Uncovering hidden local states in a quantum material

Scientists have shown evidence of local symmetry breaking in a quantum material upon heating. They believe these local states are associated with electronic orbitals that serve as orbital degeneracy lifting (ODL) "precursors" to the titanium (Ti) dimers (two molecules linked together) formed when the material is cooled to low temperature. Understanding the role of these ODL precursors may offer scientists a path toward designing materials with the desired technologically relevant properties, which typically emerge at low temperatures.

“Not surprisingly, this low-temperature regime is well studied,” said Emil Bozin, a physicist in the X-ray Scattering Group of the Condensed Matter Physics and Materials Science (CMPMS) Division at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory. “Meanwhile, the high-temperature regime remains largely unexplored because it’s associated with relatively high symmetry, which is considered uninteresting.”

New method that enables transferring materials to any substrate could push forward spintronics and related technologies

Yttrium iron garnet is a material which has special magnetic properties. A new process, developed by physicists at Martin Luther University Halle-Wittenberg (MLU), allows for it to be transferred to any material. The new method could advance the production of smaller, faster and more energy-efficient components for data storage and information processing.

Magnetic materials play a major role in the development of new storage and information technologies. Magnonics is an emerging field of research that studies spin waves in crystalline layers. Spin is a type of intrinsic angular momentum of a particle that generates a magnetic moment. The deflection of the spin can propagate waves in a solid body. "In magnonic components, electrons would not have to move to process information, which means they would consume much less energy," explains Professor Georg Schmidt from the Institute of Physics at MLU. This would also make them smaller and faster than previous technologies.

Light-induced twisting of Weyl nodes switches on giant electron current

Scientists at the U.S. Department of Energy's Ames Laboratory, along with collaborators at Brookhaven National Laboratory and the University of Alabama at Birmingham, have discovered a light-induced switch that twists the crystal lattice of the material, switching on a giant electron current that appears to be nearly dissipationless. The discovery was made in a category of topological materials that holds great promise for spintronics, topological effect transistors, and quantum computing.

Weyl and Dirac semimetals can host exotic, nearly dissipationless, electron conduction properties that take advantage of the unique state in the crystal lattice and electronic structure of the material that protects the electrons from doing so. These anomalous electron transport channels, protected by symmetry and topology, don't normally occur in conventional metals such as copper. After decades of being described only in the context of theoretical physics, there is growing interest in fabricating, exploring, refining, and controlling their topologically protected electronic properties for device applications. For example, wide-scale adoption of quantum computing requires building devices in which fragile quantum states are protected from impurities and noisy environments. One approach to achieve this is through the development of topological quantum computation, in which qubits are based on "symmetry-protected" dissipationless electric currents that are immune to noise.

Antiferromagnetic Tetragonal CuMnAs hold promise for future Spintronics and nanoelectronic devices

Researchers from the University of Nottingham are studying a new antiferromagnetic spintronic material - tetragonal CuMnAs. They say that this new material enables new device structure designs that combine Spintronic and nanoelectronic functionality - at room temperature.

An antiferromagnet is a material in which electron spin on adjacent atoms cancel each other out - and so it was considered unsuitable for Spintronics applications. However it was recently discovered that these materials have a physical phenomena that can enable memory and sensing applications.

Spintronics and Staintronics to enable ultra low power ICs

Researchers from Virginia Commonwealth University created an integrated circuit using spintronics and straintronics. The new IC design uses very little energy - in fact it could run merely by tapping the ambient energy from the environment.

The researchers say that while Spintronics promises very low power switching, when ramped up to usable processing speeds, much of that energy savings is lost because the energy is transferred to the magnet. The new design uses a special class of composite structure called multiferroics (a layer of piezoelectric material with intimate contact to a magnetostrictive nanomagnet). This generates strains in the piezoelectric layer when voltage (even a tiny voltage) is applied - which is then transferred to the magnetostrictive layer. This strain rotates the direction of magnetism, achieving the flip.

Rhomap established to develop measurement systems for Spintronics and other applications

Durham University spun-off a new company called Rhomap to develop manufacture-to-order scientific instrumentation for high precision magneto-transport measurement systems. Rhomap's instruments targets new materials and next generation semiconductors, photovoltaics, spintronics and ferromagnetic systems.

The new Ohmpoint Measurement System is a flexible research tool that offers a range of software selectable sample connection probe geometries in one system. The instrument allows users to measure resistance in two or four point geometry, sheet resistance and magneto-transport behavior, including Hall effect and magnetoresistance. The flexibility of the system also enables the user to easily select between individual measurements and batch scanning of multiple samples.

Manganites can change its stripes from fluctuating to static and back

Manganites are compounds of manganese oxides which are feature colossal magnetoresistance - and are promising candidates for spintronics applications. Researchers from the University of Colorado discovered that 2D bilayer manganite (a lanthanum strontium manganese oxide) can change its stripes from fluctuating to static and back. Magnatide stripe are regions where where the material’s electrical charges gather and concentrate. Other so-called correlated-electron materials also have stripes, including many high-temperature superconductors having the same crystal structure: arrangements of layers of atoms named for the mineral perovskite.

Manganite stripes photo

The results mean that the material can switch from a metallic state (a conductor) to an insulator. This is the first good insight into what happens to the electronic properties of a material when stripes 'fluctuate'. It establishes the existence of a distinct new phase of the material, which the researchers call fluctuating bi-stripes.

Atomtronics could be more powerful than electronics or spintronics

There's a new science called Atomtronics - which could make devices more powerful than electronics or spintronics. The idea is to use super-cooling atoms that form Bose-Einstein condensates ('gas clouds') and then use them as we use electronics, diodes and transistors. The atoms in the condensate flow as a current, which can be switched on and off like a normal circuit.

Gas Donut photo

This is still all in theory, but there are some scientists already working towards such goals - to create powerful computing devices or memory devices. This is different from spintronics, which stores information based on the spin of individual electrons, allowing each one to store two bits of data instead of one.