Related Experiment Video
Updated: Jun 5, 2026
08:18
Microscopic Visualization of Porous Nanographenes Synthesized through a Combination of Solution and On-Surface Chemistry
Published on: March 4, 2021
Surface-assisted spin Hall effect in Au films with Pt impurities
1Advanced Science Research Center, Japan Atomic Energy Agency, Tokai 319-1195, Japan.
Physical Review Letters
|January 15, 2011
Summary
Researchers discovered a new method for a giant spin-Hall effect at room temperature using surface-assisted skew scattering in platinum-doped gold films. This effect was significantly larger on the gold surface than in the bulk material.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- The spin-Hall effect (SHE) is a fundamental phenomenon in spintronics, converting charge current into a transverse spin current.
- Understanding and enhancing the SHE is crucial for developing novel spin-based electronic devices.
- Surface effects and impurity scattering are known to influence transport properties, but their role in giant SHE remains an active area of research.
Purpose of the Study:
- To investigate a novel route for achieving a giant room temperature spin-Hall effect.
- To explore the influence of surface-assisted skew scattering on the spin-Hall effect in platinum-doped gold films.
- To elucidate the underlying mechanisms responsible for the enhanced spin-Hall effect at surfaces.
Main Methods:
- Experimental synthesis and characterization of platinum-doped gold (Pt-Au) thin films with varying thicknesses.
- Electrical measurements to quantify the spin-Hall effect and determine the spin-Hall angle.
- Theoretical calculations, including ab initio and quantum Monte Carlo simulations, to model skew scattering and spin-orbit interaction.
Main Results:
- A giant spin-Hall angle (γ(S) = 0.12 ± 0.04) was experimentally observed at room temperature in Pt-doped Au films with a thickness of 10 nm.
- Theoretical calculations predicted a significant spin-Hall angle (γ(S) ≅ 0.1) on the Au (111) surface due to Pt impurities, which was considerably smaller in bulk Au.
- Enhanced spin-orbit interaction on the Au (111) surface, attributed to Pt 5d levels lifting to the Fermi level and the presence of two interaction channels, was identified as the key mechanism.
Conclusions:
- Surface-assisted skew scattering provides a novel and effective pathway to achieve a giant room temperature spin-Hall effect.
- The Au (111) surface plays a critical role in enhancing the spin-Hall effect due to localized electronic and spin-orbit coupling effects of Pt impurities.
- These findings open new avenues for designing high-performance spintronic devices utilizing surface phenomena.
