Crystalline Orientation–Dependent Spin Hall Effect in Epitaxial Platinum

We report on the spin Hall effect in epitaxial Pt films with well-defined crystalline (200), (220), and (111) orientations and smooth surfaces. The magnitude of the spin Hall effect has been determined by spin–torque ferromagnetic resonance measurements on epitaxial Pt/Py heterostructures. We observed a 54% enhancement of the charge-to-spin conversion efficiency of the epitaxial Pt when currents are applied along the in-plane <002> direction. Temperature-dependent harmonic measurements on epitaxial Pt/Co/Ni heterostructures compared to a polycrystalline Pt/Co/Ni suggest the extrinsic mechanism underlying spin Hall effect in epitaxial Pt. Our work contributes to the development of energy-efficient spintronic devices by engineering the crystalline anisotropy of non-magnetic metals.

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Modulation of spin-torque ferromagnetic resonance with a nanometer-thick platinum by ionic gating

Scientific Reports ◽

10.1038/s41598-021-01310-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ryo Ohshima ◽

Yuto Kohsaka ◽

Yuichiro Ando ◽

Teruya Shinjo ◽

Masashi Shiraishi

Keyword(s):

Hall Effect ◽

Memory Loss ◽

Spin Hall Effect ◽

Spin Torque ◽

Spin Orbit ◽

Metallic Materials ◽

Spintronic Devices ◽

Damping Parameter ◽

Inverse Spin Hall Effect ◽

High Bulk

AbstractThe spin Hall effect (SHE) and inverse spin Hall effect (ISHE) have played central roles in modern condensed matter physics especially in spintronics and spin-orbitronics, and much effort has been paid to fundamental and application-oriented research towards the discovery of novel spin–orbit physics and the creation of novel spintronic devices. However, studies on gate-tunability of such spintronics devices have been limited, because most of them are made of metallic materials, where the high bulk carrier densities hinder the tuning of physical properties by gating. Here, we show an experimental demonstration of the gate-tunable spin–orbit torque in Pt/Ni80Fe20 (Py) devices by controlling the SHE using nanometer-thick Pt with low carrier densities and ionic gating. The Gilbert damping parameter of Py and the spin-memory loss at the Pt/Py interface were modulated by ionic gating to Pt, which are compelling results for the successful tuning of spin–orbit interaction in Pt.

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Modulation of Spin-Torque Ferromagnetic Resonance with a Nanometer-Thick Platinum by Ionic Gating

10.21203/rs.3.rs-850090/v1 ◽

2021 ◽

Author(s):

Ryo Ohshima ◽

Yuto Kohsaka ◽

Yuichiro Ando ◽

Teruya Shinjo ◽

Masashi Shiraishi

Keyword(s):

Hall Effect ◽

Memory Loss ◽

Spin Hall Effect ◽

Spin Torque ◽

Spin Orbit ◽

Metallic Materials ◽

Spintronic Devices ◽

Damping Parameter ◽

Inverse Spin Hall Effect ◽

High Bulk

Abstract The spin Hall effect (SHE) and inverse spin Hall effect (ISHE) have played central roles in modern condensed matter physics especially in spintronics and spin-orbitronics, and much effort has been paid to fundamental and application-oriented research towards the discovery of novel spin-orbit physics and the creation of novel spintronic devices. However, studies on gate-tunability of such spintronics devices have been limited, because most of them are made of metallic materials, where the high bulk carrier densities hinder the tuning of physical properties by gating. Here, we show an experimental demonstration of the gate-tunable spin-orbit torque in Pt/Ni80Fe20 (Py) devices by controlling the SHE using nanometer-thick Pt with low carrier densities and ionic gating. The Gilbert damping parameter of Py and the spin-memory loss at the Pt/Py interface were modulated by ionic gating to Pt, which are compelling results for the successful tuning of spin-orbit interaction in Pt.

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Magnetization Control through the Orbital Current: Orbitronics beyond Spintronics

Physics and High Technology ◽

10.3938/phit.29.035 ◽

2020 ◽

Vol 29 (10) ◽

pp. 16-21

Author(s):

Soogil LEE ◽

Nyun Jong LEE ◽

Min-Gu KANG ◽

Byong-Guk PARK

Keyword(s):

Hall Effect ◽

Energy Efficient ◽

Experimental Results ◽

Spin Torque ◽

Magnetization Switching ◽

Spintronic Devices ◽

Material Systems

A recent study on orbital current, as a result of the orbital Hall effect, has received much attention because it is expected to provide energy-efficient electrical magnetization control in emerging spintronic devices. In this article, we introduce the concept of the orbital-current-induced spin torque, which is called the orbital torque, and discuss the advantages of using the orbital current for magnetization switching. We also summarize the recent theoretical and experimental results for the orbital current and the orbital torque in various material systems.

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