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Quantitative Studies of Spin-Momentum-Transfer-Induced Excitations in Co/Cu Multilayer Films Using Point-Contact Spectroscopy
Published
Author(s)
William Rippard, Matthew Pufall, Thomas J. Silva
Abstract
We have measured current-induced magnetic excitations in a variety of exchange-coupled Co/Cu multilayers using point-contact spectroscopy. A step in the DC resistance and corresponding peak in dV/dI are observed at a critical current Ic whose value linearly depends applied magnetic field B, in agreement with Slonczewski's theory. These features are observed for both in- and out of plane fields. Excitations in ferromagnetically-coupled films occur even without an applied field. The spin transfer efficiency is determined from the slope and intercept of Ic vs. Bapp and varied from contact-to-contact. These variations are within the range predicted by Slonczewski's theory, as bounded between the diffusive and ballistic limits for electron propagation through a point contact.
Rippard, W.
, Pufall, M.
and Silva, T.
(2003),
Quantitative Studies of Spin-Momentum-Transfer-Induced Excitations in Co/Cu Multilayer Films Using Point-Contact Spectroscopy, Applied Physics Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=30853
(Accessed October 11, 2025)