Nanowerk November 15, 2022 Researchers in China have developed a confined-van der Waals epitaxial approach to synthesizing air-stable semiconducting cobalt ferrite nanosheets with thickness down to one unit cell using a facile chemical vapor deposition process. They demonstrated hard magnetic behavior and magnetic domain evolution by means of vibrating sample magnetometry, magnetic force microscopy and magneto-optical Kerr effect measurements, which showed high Curie temperature above 390 K and strong dimensionality effect. According to the researchers their work provides possibilities for numerous novel applications in computing, sensing and information storage…read more. Open Access TECHNICAL ARTICLE
Category Archives: Spintronics
Researchers develop a material that mimics how the brain stores information
Nanowerk November 8, 2022 While a precise modulation of magnetism is achieved when voltage is applied, much more uncontrolled is the spontaneous evolution of magneto-ionic systems upon removing the electric stimuli. An international team of researchers (Spain, Italy, Belgium) has demonstrated a voltage-controllable N ion accumulation effect at the outer surface of CoN films adjacent to a liquid electrolyte, which allows for the control of magneto-ionic properties both during and after voltage pulse actuation (i.e., stimulated, and post-stimulated behavior, respectively). This effect, which takes place when the CoN film thickness is below 50 nm and the voltage pulse frequency is […]
Magnetism or no magnetism? The influence of substrates on electronic interactions
Nanowerk November 9, 2022 While technological developments of 2D MOFs typically take advantage of substrates for growth, support, and electrical contacts, investigations often ignore substrates and their dramatic influence on electronic properties. Researchers in Australia have shown how substrates alter the correlated magnetic phases in Kagome MOFs using systematic density functional theory and mean-field Hubbard calculations. They demonstrated that MOF-substrate coupling, MOF-substrate charge transfer, strain, and external electric fields are key variables, activating and deactivating magnetic phases in these materials. They used the Kagome-arranged 9,10-dicyanoanthracene molecules coordinated with copper atoms as an example. According to the researchers their findings can […]
Antiferromagnetic hybrids achieve important functionality for spintronic applications
Phys.org August 23, 2033 Previous studies have shown spin injection and detection in antiferromagnet/nonmagnetic metal bilayers; however, spin injection in these systems has been found effective only at cryogenic temperatures. An international team of researchers (USA – UC Riverside, University of Utah, Germany) has demonstrated sizable interfacial spin transport in a hybrid antiferromagnet/ferromagnet system, consisting of Cr2O3 and permalloy, which remains robust up to the room temperature. They examined their experimental data within a spin diffusion model and found evidence for the important role of interfacial magnon pumping in the signal generation. The results bridge spin-orbitronic phenomena of ferromagnetic metals […]
Breakthrough for efficient and high-speed spintronic devices
Science Daily April 25, 2022 How the spin evolves in the nanoworld on extremely short time scales, in one millionth of one billionth of a second, has remained largely mysterious. An international team of researchers (Austria, Canada, Germany, Switzerland, France, China) used a tabletop ultrafast soft X-ray microscope based on a high-energy Ytterbium laser to spatio-temporally resolve the spin dynamics inside rare earth materials. They recorded a series of snapshot images of the nanoscale rare earth magnetic structures providing rich information on the magnetic properties that are as accurate as those obtained using large-scale X-ray facilities. According to the researchers […]
Physicists show how frequencies can easily be multiplied without special circuitry
Phys.org March 10, 2022 Non-linear electronic circuits are typically used to generate the high-frequency gigahertz signals needed to operate today’s devices. An international team of researchers (Germany, Switzerland) found a way to do this within a magnetic material without the electronic components. Instead, the magnetization is excited by a low-frequency megahertz source. Using the newly discovered effect the source generates several frequency components, each of which is a multiple of the excitation frequency. These cover a range of six octaves and reach up to several gigahertz. The frequency multiplication is explained by synchronized switching of the dynamic magnetization on a […]
Graphene spintronics: 1D contacts improve mobility in nano-scale devices
Science Daily February 11, 2022 An international team of researchers (UK, Japan) used monolayer graphene encapsulated by hexagonal boron nitride in van der Waals heterostructure with one-dimensional contacts. They measured electron mobility up to 130,000cm2/Vs at low temperatures (20K or -253oC) and spin diffusion lengths approaching 20 μm. The nanoscale-wide 1D contacts allow spin injection both at room and at low temperature, with the latter exhibiting efficiency comparable with 2D tunnel contacts. At low temperature, the spin signals can be enhanced by as much as an order of magnitude by electrostatic gating, adding new functionality. According to the researchers the […]
Two-dimensional material could store quantum information at room temperature
Phys.org February 11, 2022 Spins in two-dimensional materials offer an advantage, as the reduced dimensionality enables feasible on-chip integration into devices. An international team of researchers (UK, Australia) has reported room-temperature optically detected magnetic resonance (ODMR) from single carbon-related defects in hexagonal boron nitride with up to 100 times stronger contrast than the ensemble average. They identified two distinct bunching timescales in the second-order intensity-correlation measurements for ODMR-active defects, but only one for those without an ODMR response. They observed either positive or negative ODMR signal for each defect. Based on kinematic models, they related this bipolarity to highly tunable […]
New data-decoding approach could lead to faster, smaller digital tech
Phys.org December 28, 2021 An international team of researchers (USA – University of Nebraska, University of Wisconsin, China) has shown that spin-independent conductance in compensated antiferromagnets and normal metals can be efficiently exploited in spintronics, provided their magnetic space group symmetry supports a non-spin-degenerate Fermi surface. Due to their momentum-dependent spin polarization, such antiferromagnets can be used as active elements in antiferromagnetic tunnel junctions (AFMTJs) and produce a giant tunneling magnetoresistance (TMR) effect. Using RuO2 as a representative compensated antiferromagnet exhibiting spin-independent conductance they designed a RuO2/TiO2/RuO2 (001) AFMTJ, where a globally spin-neutral charge current was controlled by the two […]
Memristive spintronic neurons: Combining two cognitive computing nano-elements into one
Nanowerk December 6, 2021 For ultrafast non-conventional computing synchronization of large spin Hall nano-oscillator arrays tuning its individual oscillators and providing built-in memory units remain substantial challenges. An international team of researchers (Sweden, India, Japan) has demonstrated the integration of a memristor into another, a spintronic oscillator. Arrays of the memristor-controlled oscillators combine the non-volatile local storage of the memristor function with the microwave frequency computation of the nano-oscillator networks and can closely imitate the non-linear oscillatory neural networks of the human brain. Using the memristor-controlled spintronic oscillator arrays, they could tune the synaptic interactions between adjacent neurons and program […]