Stacking order in a 2D magnet produces Dirac magnons

Researchers in the UK, South Korea and the U.S recently discovered that the two-dimensional layered magnet chromium triiodide (CrI3) acts as a topological magnon insulator in the absence of an external magnetic field. This result could have potential applications for so-called dissipationless spintronics in which electrons are used to transmit and store information in an ultra-fast and ultra-low power fashion.

Thanks to detailed neutron scattering measurements and fine analysis, the team has found that this phenomenon comes from the way in which the layers in the material are stacked together. That is, while a single layer of CrI3 is ferromagnetic, two stacked layers are antiferromagnetic which counterintuitively is different from that in ferromagnetic bulk.

Read the full story Posted: Nov 14,2021

Scientists develop thin-film membrane that demonstrates an intrinsic coupling between voltage and spin

Scientists at the University of Wisconsin-Madison have developed an all-thin-film membrane composite of the relaxor-ferroelectric material lead magnesium niobate-lead titanate (PMN-PT) and ferromagnetic nickel that demonstrates an intrinsic coupling between voltage and spin.

When they apply voltage to the structure, it rotates the spins of the nickel layer, a magnetoelectric effect important for spintronics. The extreme thinness of the structure allows the use of low-voltages.

Read the full story Posted: Nov 13,2021

Researchers quantify spin in WTe2

An international collaboration, led by RMIT, has quantified spin in a 2D quantum spin Hall insulator (QSHI) WTe2, a promising option for future low-energy nano-electronic and spintronic devices.

Using anisotropic magnetoresistance (AMR) to reveal the relationship between electrons’ spin and momentum, the team demonstrated the promising potential of QSHI for novel spintronic devices, and proved the value of AMR for design and development of QSHI-based spintronics.

Read the full story Posted: Nov 04,2021

Researchers launch new paradigm in magnetism and superconductivity

An international team of scientists from Austria and Germany has launched a new paradigm in magnetism and superconductivity, highlighting the effects of curvature, topology, and 3D geometry.

In modern magnetism, superconductivity and spintronics, extending nanostructures into the third dimension has become a major research avenue because of geometry-, curvature- and topology-induced phenomena. This approach provides a means to improve this and to launch novel functionalities by tailoring the curvature and 3D shape.

Read the full story Posted: Nov 04,2021

Researchers show helium can assist in controlling the spin polarization of electrons

Researchers at University of St. Andrews in the U.K., along with other institutes worldwide, have recently shown that helium can influence the spin polarization of the tunneling current and magnetic contrast of a technique known as spin-polarized scanning tunneling microscopy (SP STM). Their findings could have important implications for the development of new electronic devices.

In their previous research, the same research group investigated the magnetic order in the antiferromagnetic material iron telluride. They found that by collecting magnetic material from their sample's surface using an STM tip, they could image the sample's magnetic order.

Read the full story Posted: Nov 03,2021

Lead-Vacancy Centers in Diamonds could benefit spintronics

Researchers from Japan's Tokyo Institute of Technology, National Institute for Materials Science and National Institute of Advanced Industrial Science and Technology have found that lead-based vacancy centers in diamonds, that form after high-pressure and high-temperature treatment, are ideal for quantum networks, spintronics and quantum sensors.

The color in a diamond comes from a defect, or “vacancy,” where there is a missing carbon atom in the crystal lattice. Vacancies have long been of interest to electronics researchers because they can be used as ‘quantum nodes’ or points that make up a quantum network for the transfer of data. One of the ways of introducing a defect into a diamond is by implanting it with other elements, like nitrogen, silicon, or tin. In their recent study, the scientists from Japan demonstrated that lead-vacancy centers in diamond have the right properties to function as quantum nodes. “The use of a heavy group IV atom like lead is a simple strategy to realize superior spin properties at increased temperatures, but previous studies have not been consistent in determining the optical properties of lead-vacancy centers accurately,” says Associate Professor Takayuki Iwasaki of Tokyo Institute of Technology (Tokyo Tech), who led the study.

Read the full story Posted: Oct 15,2021

Researchers discover unconventional magnetism at the surface of Sr2RuO4

The attractive properties of Sr2RuO4, like its ability to carry lossless electrical currents and magnetic information simultaneously, make it a material with great potential for the development of future technologies like superconducting spintronics and quantum electronics. An international research team, led by scientists at the University of Konstanz, was recently able to answer one of the most interesting open questions on Sr2RuO4: why does the superconducting state of this material exhibit some features that are typically found in materials known as ferromagnets, which are considered being antagonists to superconductors?

New type of magnetism unveiled in an iconic material imageSpin polarized muon particles (red spheres with arrows) probing a new form of magnetism in the perovskite superconductor Sr2RuO4. Credit: Konstanz University

The team has found that the material hosts a new form of magnetism, which can coexist with superconductivity and exists independently of superconductivity as well.

Read the full story Posted: Oct 06,2021

Researchers discover how magnetism occurs in 2D ‘kagome’ metal-organic frameworks

Scientists from Australia's Monash University (affiliated with Fleet, the Australian research council funded ‘Arc Centre of Excellence in Future low-energy Electronics Technologies’) have discovered how magnetism occurs in 2D ‘kagome’ metal-organic frameworks, opening the door to self-assembling controllable nano-scale electronic and spintronic devices.

Kagome materials have repeating patterns of hexagons and smaller triangles, with the hexagons touching at their tips. The word 'Kagome' comes from Japanese, relating to a basket weaving pattern.

Read the full story Posted: Sep 13,2021

Researchers use graphene and other 2D materials to create a spin field-effect transistor at room temperature

Researchers at CIC nanoGUNE BRTA in Spain and University of Regensburg in Germany have recently demonstrated spin precession at room temperature in the absence of a magnetic field in bilayer graphene. In their paper, the team used 2D materials to realize a spin field-effect transistor.

Sketch of a graphene-WSe2 spin field-effect transistor imageSketch of the spin field-effect transistor. Image from article

Coherently manipulating electron spins at room temperature using electrical current is a major goal in spintronics research. This is particularly valuable as it would enable the development of numerous devices, including spin field-effect transistors. In experiments using conventional materials, engineers and physicists have so far only observed coherent spin precession in the ballistic regime and at very low temperatures. Two-dimensional (2D materials), however, have unique characteristics that could provide new control knobs to manipulate spin procession.

Read the full story Posted: Sep 08,2021

Researchers examine 'magnon' origins in 2D van der Waals magnets

Rice University researchers have confirmed the topological origins of magnons, magnetic features they discovered three years ago in a 2D material that could prove useful for encoding information in the spins of electrons.

The discovery provides a new understanding of topology-driven spin excitations in materials known as 2D van der Waals magnets. The materials are of growing interest for spintronics - for computation, storage and communications.

Read the full story Posted: Sep 04,2021