Research / Technical - Page 19

Researchers from the University of Tokyo developed a method to partially switch between specific magnetic states at Thz frequencies. The researchers used short high-frequency pulses of terahertz radiation to flip the electron spins in ferromagnetic manganese arsenide (MnAs).

Such techniques have been attempted before, but the magnitude change in the magnetization of the MnAs was too small - but in this current research a 20% change was achieved. Such a technique could be used in the future to create Thz spintronics devices - one that operate at a much faster rate compared to today's Ghz electronics devices.

Researchers from Sultan Qaboos University in Oman, Johannes Gutenberg-Universität Mainz in Germany and Nanyang Technological University in Singapore have experimentally demonstrated a breakthrough in one of the major problems blocking the adoption of magnetic domain wall memory.

When recording each fresh bit of information onto a racetrack, there is considerable uncertainty about where each magnetic domain starts and ends, and an incorrectly-written bit can easily lead to the corruption of bits. The team, led by Professor Rachid Sbiaa of Sultan Qaboos University, devised a method to overcome this difficulty by using a staggered nanowire (see figure below).

Researchers from Japan's Tohoku University have developed a nonvolatile microcontroller unit (MCU) which achieves both high performance and ultra-low power by utilizing spintronics-based VLSI design technology and STT-MRAM memory.

The researchers used several new techniques to create an efficient and fast device. Each module's power supply is controlled independently, which eliminates wasteful power consumption, while a memory controller and a reconfigurable accelerator module are used to relax data transfer bottlenecks. These new techniques enabled the researchers to achieve ultra-lower power consumptioN (47.14 uW) at 200Mhz.

Researchers from the Helmholtz-Zentrum Berlin demonstrate how it is possible to induce a magnetic order on a small region of a material by using a small electric field, instead of commonly used magnetic field.

The researchers used a wedge-shaped polycrystalline iron thin film deposited on top of a BaTiO₃ substrate (a well-known ferroelectric and ferroelastic material). Given their small size, the magnetic moments of the iron nanograins are disordered with respect to each other, this state is known as superparamagnetism.

Researchers NTU, NUS, A*STAR and the Los Alamos National Lab have demonstrated that it is possible to inject an ultra-short pulse of spin current (less than a picosecond) from a metal to a semiconductor in a very efficient way.

The researchers used a short laser pulse on cobalt (a magnetic material) - which generated a spin-polarized "swarm" of excited electrons. The spin-polarized electrons travel outside of the material - into adjacent materials. This creates an extremely efficient spin injection.

EU's Graphene Flagship project researchers fabricated graphene-based spintronics devices that utilize both electron charge and spin at room temperature.

The researchers demonstrated the spin’s feasibility for bridging distances of up to several micrometres - which they say could open the door to single-chip devices that integrate logic and memory.

Researchers from the University of Utah developed two spintronics devices based on perovskite materials. The researchers use these new devices to demonstrate the high potential of perovksites for spintronics systems. This is a followup to the exciting results announced in 2017 by the same group that showed advantages of perovskites for spintronics.

The researchers use an organic-inorganic hybrid perovskite material that has a heavy lead atom that features strong spin-orbit coupling and a long injected spin lifetime.The first device is a spintronic LED which works with a magnetic electrode instead of an electron-hole electrode. The perovskite LED lights up with circularly polarized electroluminescence.

Researchers from the University of Gothenburg have succeeded to produce spin wave overtones for the first time, which could enable faster wireless data communication based on spintronics devices.

Spintronic oscillators are devices in which spin waves are used to generate microwave signals in the gigahertz range. The new research shows how it is possible to produce spintronic oscillators that strengthen spin wave signals in several steps. This makes it possible to generate very high microwave frequencies with short wavelengths for use in spintronics and magnonics.

Researchers from the UK's Manchester University have explored opportunities presented by hexagonal boron nitride (hBN) as a prototypical high-quality two-dimensional insulator that can be used both as a barrier in MTJs and as for spin injection in lateral spin valves.

The research revealed the effect of point defects inevitably present in mechanically exfoliated hBN on the tunnel magnetoresistance of Co-hBN-NiFe MTJs. In particular, the researchers observe a marked enhancement of the magnetoresistance of the junction at well-defined bias voltages, indicating resonant tunneling through magnetic or 'spin-polarized' defect states.

Researchers of the NanoBioMedical center at Adam Mickiewicz University in Poznan- Poland, in collaboration with the University of Barcelona in Spain, have recently reported on the room temperature multiferroic behavior of Bismuth Iron Manganite (Bi(Fe_0.5Mn_0.5)O₃) thin films, with a thickness below 40nm.

Multiferroic materials are promising for electronics due to the possibility of affecting their magnetic properties by electric means. In their article the team has not only shown the interdependence of both magnetic and electric properties at room temperature but has also shown the exceptional low magnetic damping of this material, making it one of the only known ferromagnetic and ferroelectric multiferroic with low damping.