| Author(s): |
William H. Rippard; Matthew R. Pufall; Thomas J. Silva; |
| Title: |
Quantitative Studies of Spin-Momentum-Transfer-Induced Excitations in Co/Cu Multilayer Films Using Point-Contact Spectroscopy |
| Published: |
February 24, 2003 |
| 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. |
| Citation: |
Applied Physics Letters |
| Volume: |
82 |
| Issue: |
8 |
| Pages: |
pp. 1260 - 1262 |
| Keywords: |
point contact;SMT;spin excitations;spin momentum transfer; |
| Research Areas: |
Spintronics |
| PDF version: |
 Click here to retrieve PDF version of paper (107KB) |
