Spin-Orbit and Magnetic Proximity-Induced Phenomena in Nanostructures Comprising Transition Metals, Insulators and 2D Materials

Mairbek Chshiev, Univ. Grenoble Alpes, CEA, CNRS, SPINTEC

June 26, 2020

In recent years, spin-orbit coupling based phenomena at interfaces comprising ferromagnetic (FM) metal, oxide (O) and nonmagnetic metal (NM) have been an object of great interest for spintronics including spin-orbitronics [1]. At the same time, a major attention of scientific community has been devoted to developments of emerging field of 2D and graphene spintronics [2]. In this talk I will provide theoretical insights into perpendicular magnetic anisotropy (PMA) [1,3-8], Dzyaloshinskii-Moriya interaction (DMI) [9-13] and magnetic proximity-induced phenomena [13-17] at interfaces comprising transition metals, insulators and graphene.

First, mechanisms of PMA [1,3-5] and its variation by applied electric field (VCMA) [6] or by ionic migration [7] at FM/O interfaces are unveiled using first-principles approaches. Strong enhancement of the PMA of Co films at Co/graphene interfaces is also discussed [8]. Next, microscopic mechanisms of DMI behavior at FM/NM [9], FM/O [9,10] and FM/graphene [11] interfaces are elucidated. Several approaches for DMI enhancement using trilayers with different FM/NM or FM/O interfaces [10] important for observation of room temperature skyrmions [12] are proposed. Possibility of controlling DMI by electric field (VCDMI) at NM/FM/O [10] or by hydrogenation at FM/graphene interfaces [13] are introduced as well. Finally, I will discuss magnetic phenomena in graphene induced by proximity of different insulators including europium chalcogenides [14,15], yttrium iron garnet (YIG), cobalt ferrite (CFO) [15] and bismuth ferrite (BFO) [17]. Large exchange-splitting values induced in graphene allow introduction of several proximity induced transport phenomena named proximity electro- (PER), magneto- (PMR), and multiferroic (PMER) resistance effects [16,17].

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