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arXiv · 2205.06859

Large-Area Intercalated 2D-Pb/Graphene Heterostructure as a Platform for Generating Spin-Orbit Torque

Alexander Vera·Boyang Zheng·Wilson Yanez·Kaijie Yang·Seong Yeoul Kim·Xinglu Wang·Jimmy C. Kotsakidis·Hesham El-Sherif·Gopi Krishnan·Roland J. Koch·T. Andrew Bowen·Chengye Dong·Yuanxi Wang·Maxwell Wetherington·Eli Rotenberg·Nabil Bassim·Adam L. Friedman·Robert M. Wallace·Chaoxing Liu·Nitin Samarth·Vincent H. Crespi·Joshua A. Robinson
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Abstract

A scalable platform to synthesize ultrathin heavy metals may enable high efficiency charge-to-spin conversion for next-generation spintronics. Here we report the synthesis of air-stable, epitaxially registered monolayer Pb underneath bilayer graphene on SiC (0001) by confinement heteroepitaxy (CHet). Diffraction, spectroscopy, and microscopy reveal CHet-based Pb intercalation predominantly exhibits a mottled hexagonal superstructure due to an ordered network of Frenkel-Kontorova-like domain walls. The system's air stability enables ex-situ spin torque ferromagnetic resonance (ST-FMR) measurements that demonstrate charge-to-spin conversion in graphene/Pb/ferromagnet heterostructures with a 1.5x increase in the effective field ratio compared to control samples.

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Alexander Vera, Boyang Zheng, Wilson Yanez, Kaijie Yang, Seong Yeoul Kim, Xinglu Wang, Jimmy C. Kotsakidis, Hesham El-Sherif, Gopi Krishnan, Roland J. Koch, T. Andrew Bowen, Chengye Dong, Yuanxi Wang, Maxwell Wetherington, Eli Rotenberg, Nabil Bassim, Adam L. Friedman, Robert M. Wallace, Chaoxing Liu, Nitin Samarth, Vincent H. Crespi, Joshua A. Robinson. 2022-05-13. Large-Area Intercalated 2D-Pb/Graphene Heterostructure as a Platform for Generating Spin-Orbit Torque. https://doi.org/10.1021/acsnano.4c04075

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