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

Area of Science:

• Condensed Matter Physics
• Spintronics
• Spin-Orbitronics

Background:

• The spin Hall effect (SHE) and inverse spin Hall effect (ISHE) are crucial in spintronics and spin-orbitronics.
• Gate-tunability studies in these devices are limited due to high carrier densities in metallic materials.
• Controlling spin-orbit interactions is key for developing advanced spintronic devices.

Purpose of the Study:

• To experimentally demonstrate gate-tunable spin-orbit torque in platinum/nickel-iron (Pt/Py) devices.
• To investigate the modulation of the spin Hall effect (SHE) using ionic gating.
• To explore the impact of gating on material properties relevant to spintronics.

Main Methods:

• Utilized nanometer-thick platinum (Pt) layers with low carrier densities.
• Employed ionic gating to control the physical properties of the Pt layer.
• Fabricated and measured Pt/Ni₈₀Fe₂₀ (Py) heterostructures.

Main Results:

• Successfully demonstrated gate-tunable spin-orbit torque in Pt/Py devices.
• Showed that ionic gating modulates the Gilbert damping parameter of Py.
• Observed modulation of spin-memory loss at the Pt/Py interface via ionic gating.

Conclusions:

• Ionic gating provides an effective method to tune spin-orbit interactions in Pt.
• The findings enable control over spintronic properties, paving the way for novel devices.
• Demonstrates a pathway for overcoming limitations in gate-tunable spintronics.