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arXiv · 2109.14503

Nonreciprocal transport in a Rashba ferromagnet, delafossite PdCoO$_2$

Jin Hong Lee·Takayuki Harada·Felix Trier·Lourdes Marcano·Florian Godel·Sergio Valencia·Atsushi Tsukazaki·Manuel Bibes
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Abstract

Rashba interfaces yield efficient spin-charge interconversion and give rise to nonreciprocal transport phenomena. Here, we report magnetotransport experiments in few-nanometer-thick films of PdCoO$_2$, a delafossite oxide known to display a large Rashba splitting and surface ferromagnetism. By analyzing the angle dependence of the first- and second-harmonic longitudinal and transverse resistivities, we identify a Rashba-driven unidirectional magnetoresistance that competes with the anomalous Nernst effect below the Curie point. We estimate a Rashba coefficient of 0.75 {\pm} 0.3 eV {\AA} and argue that our results qualify delafossites as a new family of oxides for nano-spintronics and spin-orbitronics, beyond perovskite materials.

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Jin Hong Lee, Takayuki Harada, Felix Trier, Lourdes Marcano, Florian Godel, Sergio Valencia, Atsushi Tsukazaki, Manuel Bibes. 2021-09-29. Nonreciprocal transport in a Rashba ferromagnet, delafossite PdCoO$_2$. https://doi.org/10.1021/acs.nanolett.1c02756

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