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arXiv · 2306.10673

Magneto-Optical Detection of the Orbital Hall Effect in Chromium

Igor Lyalin·Sanaz Alikhah·Marco Berritta·Peter M. Oppeneer·Roland K. Kawakami
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Abstract

The orbital Hall effect has been theoretically predicted but its direct observation is a challenge. Here, we report the magneto-optical detection of current-induced orbital accumulation at the surface of a light 3$d$ transition metal, Cr. The orbital polarization is in-plane, transverse to the current direction, and scales linearly with current density, consistent with the orbital Hall effect. Comparing the thickness-dependent magneto-optical measurements with $\textit{ab initio}$ calculations, we estimate an orbital diffusion length in Cr of $6.6\pm 0.6$ nm.

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Igor Lyalin, Sanaz Alikhah, Marco Berritta, Peter M. Oppeneer, Roland K. Kawakami. 2023-06-19. Magneto-Optical Detection of the Orbital Hall Effect in Chromium. https://doi.org/10.1103/physrevlett.131.156702

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