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arXiv · 1809.10475

Absence of a giant spin Hall effect in plasma-hydrogenated graphene

Tobias Völkl·Denis Kochan·Thomas Ebnet·Sebastian Ringer·Daniel Schiermeier·Philipp Nagler·Tobias Korn·Christian Schüller·Jaroslav Fabian·Dieter Weiss·Jonathan Eroms
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Abstract

The weak spin-orbit interaction in graphene was predicted to be increased, e.g., by hydrogenation. This should result in a sizable spin Hall effect (SHE). We employ two different methods to examine the spin Hall effect in weakly hydrogenated graphene. For hydrogenation we expose graphene to a hydrogen plasma and use Raman spectroscopy to characterize this method. We then investigate the SHE of hydrogenated graphene in the H-bar method and by direct measurements of the inverse SHE. Although a large nonlocal resistance can be observed in the H-bar structure, comparison with the results of the other method indicate that this nonlocal resistance is caused by a non-spin-related origin.

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Tobias Völkl, Denis Kochan, Thomas Ebnet, Sebastian Ringer, Daniel Schiermeier, Philipp Nagler, Tobias Korn, Christian Schüller, Jaroslav Fabian, Dieter Weiss, Jonathan Eroms. 2018-09-27. Absence of a giant spin Hall effect in plasma-hydrogenated graphene. https://doi.org/10.1103/physrevb.99.085401

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