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Damping-like Torque in Monolayer 1T-TaS$_2$

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 نشر من قبل Sajid Husain
 تاريخ النشر 2020
  مجال البحث فيزياء
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A damping-like spin orbit torque (SOT) is a prerequisite for ultralow power spin logic devices. Here, we report on the damping-like SOT in just one monolayer of the conducting transition metal dichalcogenide (TMD) TaS$_2$ interfaced with a NiFe (Py) ferromagnetic layer. The charge-spin conversion efficiency is found to be 0.25$pm$0.03 and the spin Hall conductivity (2.63 $times$ 10$^5$ $frac{hbar}{2e}$ $Omega^{-1}$ m$^{-1}$) is found to be superior to values reported for other TMDs. The origin of this large damping-like SOT can be found in the interfacial properties of the TaS$_2$/Py heterostructure, and the experimental findings are complemented by the results from density functional theory calculations. The dominance of damping-like torque demonstrated in our study provides a promising path for designing next generation conducting TMD based low-powered quantum memory devices.

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