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 […]
Category Archives: Spintronics
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
Graphene and 2D materials could move electronics beyond ‘Moore’s Law’
Science Daily June 3, 2020 After the first demonstration of spin transport in graphene in 2007 at room temperature, it was quickly realized that this novel material was relevant for both fundamental spintronics and future applications. In this colloquium an international team of researchers (Switzerland, USA – Columbia University, Spain, Singapore, the Netherlands, UK) reviews recent theoretical and experimental advances on electronic spin transport in graphene and related 2D materials. They focus on emergent phenomena in van der Waals heterostructures and the new perspectives provided by them, including proximity-enabled spin-orbit effects, the coupling of electronic spin to light, electrical tunability, […]
Scientists take steps to create a ‘racetrack memory,’ potentially enhancing data storage
Science Daily May 5, 2020 A team of researchers in US ( New York University, University of Virginia, NIST, University of Colorado, Boulder) are working to supplant current methods of mass data storage with a skyrmion racetrack memory which reconfigures magnetic fields in innovative ways. It has improved density of information storage, faster operation, and lower energy use. Skyrmions can be moved by applying an external stimulus, such as a current pulse. They are only stable in very specific material environments, so identifying the ideal materials that can host skyrmions and the circumstances under which they are created is a […]
Toward a more energy-efficient spintronics
EurekAlert April 22, 2020 In order to generate and detect spin currents, spintronics traditionally uses ferromagnetic materials whose magnetization switching consume high amounts of energy. Researchers in France have demonstrated an alternative strategy to achieve low-power spin detection in a non-magnetic system by harnessing the electric-field-induced ferroelectric-like state of strontium titanate to manipulate the spin–orbit properties of a two-dimensional electron gas and efficiently convert spin currents into positive or negative charge currents, depending on the polarization direction. The research opens the way to the electric-field control of spin currents and to ultralow-power spintronics…read more. TECHNICAL ARTICLE
Van der Waals magnets, a material for future semiconductors
Nanowerk February 16, 2020 When van der Waals materials are combined with other 2D materials, they can create new materials that show previously undiscovered properties. However, most van der Waals magnetic materials have some constraints in terms of spintronics application because of their low Curie temperature and high coercivity making them unsuitable for use in certain devices. An international team of researchers (South Korea, USA – Brookhaven National Laboratory, Lawrence Berkeley National Laboratory) found that Fe3–xGeTe2 nanoflakes show a significant suppression of the magnetic anisotropy with hole doping. Electronic structure measurements and calculations revealed that the chemical potential shift associated […]
Detection of very high frequency magnetic resonance could revolutionize electronics
Phys.org January 27, 2020 A team of researchers in the US (UC Riverside, UC Santa Barbara) generated spin current in an antiferromagnet and were able to detect it electrically. They used terahertz radiation to pump up magnetic resonance in chromia to facilitate its detection. Although antiferromagnets are statically uninteresting, they are dynamically interesting. Electron spin precession in antiferromagnets is much faster than in ferromagnets, resulting in frequencies that are two-three orders of magnitude higher than the frequencies of ferromagnets—thus allowing faster information transmission…read more. TECHNICAL ARTICLE
Computing with molecules: A big step in molecular spintronics
EurekAlert December 23, 2019 An international team of researchers (Germany, Switzerland, France) integrated a spin switching functionality into robust complexes, relying on the mechanical movement of an axial ligand strapped to the porphyrin ring. They demonstrated reversible interlocked switching of spin and coordination induced by electron injection on Ag(111) for this class of compounds. The stability of the two spin and coordination states of the molecules exceeds days. The potential applications of this switching concept go beyond the spin functionality and may turn out to be useful for controlling the catalytic activity of surfaces…read more. TECHNICAL ARTICLE
Paving the way for spintronic RAMs: A deeper look into a powerful spin phenomenon
Science Daily December 26, 2019 Extensive studies on Unidirectional spin Hall magnetoresistance (USMR) in metallic bilayers has found that its magnitude (∼10−5) is too small for practical applications. An international team of researchers(Japan,Vietnam) has demonstrated a giant USMR effect in a heterostructure of BiSb topological insulator – GaMnAs ferromagnetic semiconductors. They obtained a large USMR ratio of 1.1% and found that this giant USMR is governed not by the giant magnetoresistance like spin-dependent scattering but by magnon emission/absorption and strong spin-disorder scattering in the GaMnAs layer. Their results present a novel strategy to exploit spin-related phenomena in topological materials, which […]