Magnetic skyrmions are topologically protected spin textures of great interest for nanoscale information storage and processing. However, stabilizing small skyrmions without applying an external magnetic field remains challenging. This study employs a thin ferromagnetic layer exchange-biased by an antiferromagnetic film to stabilize ferromagnetic skyrmions down to 30 nm in diameter, at zero magnetic field. In […]
Read moreMetamagnetism of Weakly Coupled Antiferromagnetic Topological Insulators (July 06th, 2020)
Layered magnetic topological insulators are candidate to unveil novel electronic phases controlled by the magnetization. In MnBi4Te7, we evidenced a transition from an antiferromagnetic to a ferromagnetic-like metamagnetic state, possibly realizing the quantum anomalous Hall regime in ultra-thin films above 1K. 3D topological insulators ideally have an insulating bulk and 2D gapless topological surface states […]
Read moreSpin-orbitronics at a topological insulator-semiconductor interface (July 02nd, 2020)
Topological insulators (TI) represent a new class of insulating materials hosting metallic surface states. Moreover, those surface states exhibit a Dirac cone energy dispersion where the strong spin-orbit coupling leads to a helical spin texture at the Fermi level. This property can be exploited to detect spin currents in conventional semiconductors like silicon or germanium. […]
Read moreCoherent long-range coupling between spins by chiral phonons (May 04th, 2020)
We present experimental evidence for coherent long-distance transport of angular momentum inside a non-magnetic dielectric via the coupling to circularly polarized sound waves that exceeds previous benchmarks set by magnon diffusion by orders of magnitude. The vision of spintronics is to use the spin of an electron rather than its charge to allow computers and […]
Read moreAll-optical switching of magnetization in Tb/Co-multilayer based electrodes (April 30th, 2020)
This work reports the development of perpendicular magnetic tunnel junctions incorporating a stack of Tb/Co nanolayers whose magnetization can be all-optically controlled via helicity-independent single-shot switching. Toggling of the magnetization of the Tb/Co electrode was achieved using either 60 femtosecond-long or 5 picosecond-long laser pulses, with incident fluences down to 3.5 mJ/cm2. Ever since the […]
Read moreNon-volatile electric control of spin–charge conversion in a SrTiO3 Rashba system (April 22nd, 2020)
Electron spin—a fundamentally quantum property—is central to spintronics, a technology that revolutionized data storage, and that could play a major role in creating new computer processors. In order to generate and detect spin currents, spintronics traditionally uses ferromagnetic materials whose magnetization switching consume high amounts of energy. In the April 22, 2020 issue of Nature, […]
Read moreReducing the impact of operating temperature in magnetic memory thanks to perpendicular shape anisotropy (April 01st, 2020)
MRAM is a type of nonvolatile memory that stores the binary information through the magnetic configuration of its main building block: the Magnetic Tunnel Junction (MTJ). In the last decade, the use of perpendicular anisotropy existing at the tunnel barrier interface, allowed to improve MRAM manufacturability. However, the thermal sensitivity of the interfacial anisotropy is […]
Read moreSpin accumulation dynamics in spintronic devices in the terahertz regime (March 26th, 2020)
Spin accumulation phenomena frequently occur in spintronic devices due to the difference of electrical resistivities of spin-up and spin-down electrons in magnetic materials. They are balanced by spin relaxation phenomena. These phenomena take place in a diffusive regime which involves numerous individual scattering events. Consequently, although the time scale of elastic electron scattering in metals […]
Read moreObservation of Large Unidirectional Rashba Magnetoresistance in Ge(111) (March 10th, 2020)
Relating magnetotransport properties to specific spin textures at surfaces or interfaces is an intense field of research nowadays. Here, we investigate the variation of the electrical resistance of Ge(111) under the application of an external magnetic field. We find a magnetoresistance term that is linear in current density j and magnetic field B, reaching 0.5 […]
Read moreExperimental evidence of the valley Nernst effect in WSe2 (March 06th, 2020)
The Hall effect can be extended by inducing a temperature gradient in lieu of electric field that is known as the Nernst effect. After the discovery of the spin Nernst effect, the collection would not be complete without mentioning the valley degree of freedom benchmarked by the observation of the valley Hall effect in transition […]
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