Spintronics: New production method makes crystalline microstructures universally usable

Science Daily  February 23, 2021 Based on a recently developed method that allows the fabrication of freestanding monocrystalline YIG bridges on gadolinium-gallium-garnet, researchers in Germany have developed a process that allows the transfer of monocrystalline yttrium-iron-garnet microstructures onto virtually any kind of substrate. The bridges’ spans are detached from the substrate by a dry etching process and immersed in a watery solution. Using drop-casting, the immersed YIG platelets can be transferred onto the substrate of choice, where the structures finally can be reattached and, thus, be integrated into complex devices or experimental geometries. They demonstrated that the structures retain their […]

Researchers demonstrate the potential of a new quantum material for creating two spintronic technologies

Phys.org  February 3, 2021 Finding materials with the exact characteristics necessary to fabricate Antiferromagnetic (AFM) spintronics has so far proved to be highly challenging. An international team of researchers (USA – UC Berkeley, Lawrence Berkeley National Laboratory, National High Magnetic Field Laboratory, UCLA, Israel) has identified a new quantum material (Fe1/3 + δNbS2) that could be used to fabricate AFM spintronic devices. They demonstrated that antiferromagnetic switching in the intercalated transition-metal dichalcogenide (TMD)-based compounds have a huge ‘exchange bias’, single-pulse saturation and a significantly lower activation energy. They showed that the coexistence of spin glass and antiferromagnetic order allows a […]

Researchers from NUS create ‘whirling’ nano-structures in anti-ferromagnets

EurekAlert  February 4, 2021 Special magnetic nano-patterns in anti-ferromagnets that are shaped as whirls or vortices would be quite useful, as they are very stable structures and can potentially be moved along magnetic ‘race tracks’ at speeds of a few kilometres per second. To realize anti-ferromagnetic whirls an international team of researchers (Singapore, UK, USA – University of Wisconsin) combined high-quality film synthesis from materials engineering, phase transitions from physics and topology from mathematics. To grow these materials they fired a laser at iron-oxide. By using ultra-short pulses of laser, they created a hot vapour of atomic particles that formed […]

The long-range transport of deconfined magnetic hedgehogs

Phys.org  January 18, 2021 Using magnetic insulators to achieve long-range transport of spins has proved highly challenging. Researchers at UCLA resorted to topological spin textures rather than spins themselves for the purpose of long-range transport. The magnetic hedgehog is one type of topologically protected spin texture that generically exits in three-dimensional magnets. The researchers showed that the hedgehog current is a well conserved quantity and can be explored to achieve long-range transport in magnetic insulators. The study is based on the theoretical construct topological conservation law, which allowed the researchers to leverage the idea of hydrodynamics of topological spin textures. […]

The changing paradigm of next-generation semiconductor memory development

Nanowerk  January 12, 2021 It has been reported that spins are formed inside a nanomagnet if electric current is applied to the nanomagnet. There have been no studies on the physical results of these spins. Researchers in South Korea have established a theoretical system by developing a spin diffusion equation that describes the spin conductance in magnetic materials. They discovered that when the spins formed by electric current is emitted to the outside, only the sign is opposite to that of the spins injected from the outside, and the effects are the same. Therefore, the directions of the N pole […]

Electrical spin filtering the key to ultra-fast, energy-efficient spintronics

Science Daily  December 4, 2020 All-electrical generation of spin has already been successfully demonstrated. However, detection of spin-to-charge conversion has always required a large range of magnetic fields, thus limiting the speed and practicality. An international team of researchers (Australia, Switzerland, Japan, Slovenia, UK, Singapore) introduces a new method for detecting spin accumulation using a spin filter, which separates different spin orientations based on their energies. They demonstrated a general method that exploits the nonlinear interactions between spin and charge currents to perform all-electrical, rapid, and noninvasive detection of spin accumulation without the need for a magnetic field. They used […]

Ultrafast electrons in magnetic oxides: A new direction for spintronics?

Science Daily  August 19, 2020 Special metal oxides could one day replace semiconductor materials that are commonly used today in processors. Until recently it had not been clear how the electron transfer across the band gap coupled with the spin of the magnetic oxide occurs. An international team of researchers (Germany, USA – research institute, Switzerland) was able to excite an electron to lift it across the band gap in nickel oxide. They also observed how the information was then transferred to the magnetic system. This enabled the team to identify a previously unknown ultrafast coupling mechanism that occurs on […]

An electrical switch for magnetism

Phys.org  August 6, 2020 Electrical control of magnetism in van der Waals ferromagnetic semiconductors is an important step in creating novel spintronic devices capable of processing and storing information. Using an electric double-layer transistor device, an international team of researchers (Singapore, UK, China) discovered that the magnetism of a magnetic semiconductor, Cr2Ge2Te6, shows exceptionally strong response to applied electric fields. With electric fields applied, the material was found to exhibit ferromagnetism at temperatures up to 200 K (-73°C). At such temperatures, ferromagnetic order is normally absent in this material. Their analysis suggests that heavy doping promotes a double-exchange mechanism that […]

Magnetic memory states go exponential

EurekAlert  July 9, 2020 When spintronic devices are used for storing data, the number of stable states sets an upper limit on memory capacity. Researchers in Israel have shown that relatively simple structures can support exponential number of magnetic states – much greater than previously thought. They studied structures that are magnetic thin films patterned in the form of N crossing ellipses which have two to the power of 2N magnetization states. The researchers demonstrated switching between the states by generating spin currents. The finding may pave the way to multi-level magnetic memory with extremely large number of states per […]

Extensive review of spin-gapless semiconductors: Next-generation spintronics candidates

EurekAlert  June 26, 2020 The spin‐gapless semiconductors (SGSs) are a new class of zero‐gap materials which have fully spin polarized electrons and holes. They bridge the zero‐gap materials and the half‐metals. The band structures of the SGSs can have two types of energy dispersion: Dirac linear dispersion and parabolic dispersion. Researchers in Australia review both methods in different material systems and the concepts of the SGS, novel spin and charge states, and the potential applications of SGSs in next‐generation spintronic devices…read more. TECHNICAL ARTICLE