Enhancement of spin Hall angle by an order of magnitude via Cu intercalation in MoS$_2$/CoFeB heterostructures

Abhisek Mishra; Pritam Das; Rupalipriyadarsini Chhatoi; Soubhagya Dash; Shubhransu Sahoo; Kshitij Singh Rathore; Pil-Ryung Cha; Seung-Cheol Lee; Satadeep Bhattacharjee; Subhankar Bedanta

arXiv · 2411.18582

Enhancement of spin Hall angle by an order of magnitude via Cu intercalation in MoS$_2$/CoFeB heterostructures

Abhisek Mishra·Pritam Das·Rupalipriyadarsini Chhatoi·Soubhagya Dash·Shubhransu Sahoo·Kshitij Singh Rathore·Pil-Ryung Cha·Seung-Cheol Lee·Satadeep Bhattacharjee·Subhankar Bedanta

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Abstract

Transition metal dichalcogenides (TMDs) are a novel class of quantum materials with significant potential in spintronics, optoelectronics, valleytronics, and opto-valleytronics. TMDs exhibit strong spin-orbit coupling, enabling efficient spin-charge interconversion, which makes them ideal candidates for spin-orbit torque-driven spintronic devices. In this study, we investigated the spin-to-charge conversion through ferromagnetic resonance in MoS$_2$/Cu/CoFeB heterostructures with varying Cu spacer thicknesses. The conversion efficiency, quantified by the spin Hall angle, was enhanced by an order of magnitude due to Cu intercalation. Magneto-optic Kerr effect microscopy confirmed that Cu did not significantly modify the magnetic domains, indicating its effectiveness in decoupling MoS$_2$ from CoFeB. This decoupling preserves the spin-orbit coupling (SOC) of MoS$_2$ by mitigating the exchange interaction with CoFeB, as proximity to localized magnetization can alter the electronic structure and SOC. First-principles calculations revealed that Cu intercalation notably enhances the spin Berry curvature and spin Hall conductivity, contributing to the increased spin Hall angle. This study demonstrates that interface engineering of ferromagnet/TMD-based heterostructures can achieve higher spin-to-charge conversion efficiencies, paving the way for advancements in spintronic applications.

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Abhisek Mishra, Pritam Das, Rupalipriyadarsini Chhatoi, Soubhagya Dash, Shubhransu Sahoo, Kshitij Singh Rathore, Pil-Ryung Cha, Seung-Cheol Lee, Satadeep Bhattacharjee, Subhankar Bedanta. 2024-11-27. Enhancement of spin Hall angle by an order of magnitude via Cu intercalation in MoS$_2$/CoFeB heterostructures. https://arxiv.org/abs/2411.18582

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