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arXiv · 1806.08260

Spin transfer torque induced paramagnetic resonance

Alexey M. Shakirov·Alexey N. Rubtsov·Pedro Ribeiro
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Abstract

We show how the spin-transfer torque generated by an ac voltage may be used to excite a paramagnetic resonance of an atomic spin deposited on a metallic surface. This mechanism is independent of the environment of the atom and may explain the ubiquity of the paramagnetic resonance reported by Baumann $\textit{et al.}$ [$\href{http://dx.doi.org/10.1126/science.aac8703}{Science \textbf{350}, 417 (2015)}$]. The current and spin dynamics are modeled by a time-dependent Redfield master equation generalized to account for the periodic driven voltage. Our approach shows that the resonance effect is a consequence of the nonlinearity of the coupling between the magnetic moment and the spin-polarized current which generates a large second-harmonic amplitude that can be measured in the current signal.

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Alexey M. Shakirov, Alexey N. Rubtsov, Pedro Ribeiro. 2019-03-04. Spin transfer torque induced paramagnetic resonance. https://doi.org/10.1103/physrevb.99.054434

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