Advanced Materials · 2020 · 134 citations · 18 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsMagnetic MaterialsMaterials PhysicsFerromagnetic MaterialsFerromagnetismMagnetic Properties Of SolidsMagnetism In SolidsSpintronic MaterialsSpintronicsCurrent-induced Magnetization SwitchingHall EffectHeterostructuresMagnetic PropertiesMagnetization DynamicsSpin Hall EffectSpontaneous MagnetizationVan Der Waals Heterostructures
Electrical manipulation of magnetic properties in van der Waals ferromagnets is essential for their integration into future spintronics devices. The study aims to manipulate the magnetization of thin Cr₂Ge₂Te₆ flakes using an in‑plane magnetic field and a charge current through Ta. The authors investigate Cr₂Ge₂Te₆/Ta heterostructures by measuring anomalous Hall effect while applying an in‑plane magnetic field and a charge current through Ta to generate spin Hall torque. Thinner Cr₂Ge₂Te₆ flakes show stronger out‑of‑plane hysteresis, and with 20 mT in‑plane fields a charge current density as low as 5 × 10⁵ A cm⁻² switches the magnetization—two orders of magnitude lower than for CoFeB—highlighting the low‑power potential of 2D ferromagnets for memory and logic.
Abstract Being able to electrically manipulate the magnetic properties in recently discovered van der Waals ferromagnets is essential for their integration in future spintronics devices. Here, the magnetization of a semiconducting 2D ferromagnet, i.e., Cr 2 Ge 2 Te 6 , is studied using the anomalous Hall effect in Cr 2 Ge 2 Te 6 /tantalum heterostructures. The thinner the flakes, hysteresis and remanence in the magnetization loop with out‐of‐plane magnetic fields become more prominent. In order to manipulate the magnetization in such thin flakes, a combination of an in‐plane magnetic field and a charge current flowing through Ta—a heavy metal exhibiting giant spin Hall effect—is used. In the presence of in‐plane fields of 20 mT, charge current densities as low as 5 × 10 5 A cm –2 are sufficient to switch the out‐of‐plane magnetization of Cr 2 Ge 2 Te 6 . This finding highlights that current densities required for spin‐orbit torque switching of Cr 2 Ge 2 Te 6 are about two orders of magnitude lower than those required for switching nonlayered metallic ferromagnets such as CoFeB. The results presented here show the potential of 2D ferromagnets for low‐power memory and logic applications.
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Layer-dependent ferromagnetism in a van der Waals crystal down to the monolayer limit
Bevin Huang, Genevieve Clark, Efrén Navarro‐Moratalla et al. · Nature · 2017 · 5.9K citations · Full text
Spin-Torque Switching with the Giant Spin Hall Effect of Tantalum
Luqiao Liu, Chi‐Feng Pai, Yi Li et al. · Science · 2012 · 4.1K citations · Full text
Natural Sciences, Materials Engineering, Materials Science +17
Electrical control of 2D magnetism in bilayer CrI3
Bevin Huang, Genevieve Clark, Dahlia Klein et al. · Nature Nanotechnology · 2018 · 1.4K citations · Full text
Controlling magnetism in 2D CrI3 by electrostatic doping
Nature Nanotechnology · 2018 · 1.1K citations · Full text