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arXiv · 2210.02283

Detection of long-range orbital-Hall torques

Arnab Bose·Fabian Kammerbauer·Rahul Gupta·Dongwook Go·Yuriy Mokrousov·Gerhard Jakob·Mathias Klaeui
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Abstract

We report and quantify a large orbital-Hall torque generated by Nb and Ru, which we identify from a strong dependence of torques on the ferromagnets. This is manifested as a sign reversal and strong enhancement in the damping-like torques measured in Nb (or Ru)/Ni bilayers as compared to Nb (or Ru)/FeCoB bilayers. The long-range nature of orbital transport in the ferromagnet is revealed by the thickness dependences of Ni in Nb (or Ru)/Ni bilayers which are markedly different from the regular spin absorption in the ferromagnet that takes place within a few angstroms and thus it uniquely distinguishes the orbital Hall torque from the spin Hall torque.

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Arnab Bose, Fabian Kammerbauer, Rahul Gupta, Dongwook Go, Yuriy Mokrousov, Gerhard Jakob, Mathias Klaeui. 2022-10-05. Detection of long-range orbital-Hall torques. https://doi.org/10.1103/physrevb.107.134423

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