Abstract
We report on a highly efficient spin diode effect in exchange-biased spin-valve giant-magnetoresistance (GMR) strips. In such multilayer structures, the symmetry of the current distribution along the vertical direction is broken and, as a result, a noncompensated Oersted field acting on the magnetic free layer appears. This field in turn is a driving force of magnetization precessions. Due to the GMR effect, the resistance of the strip oscillates following the magnetization dynamics. This leads to rectification of the applied radio-frequency current and induces a direct-current voltage . We present a theoretical description of this phenomenon and calculate the spin diode signal as a function of frequency, external magnetic field, and angle at which the external field is applied. Satisfactory quantitative agreement between theoretical predictions and experimental data has been achieved. Finally, we show that the spin diode signal in GMR devices is significantly stronger than in the anisotropic magnetoresistance permalloy-based devices.
1 More- Received 27 October 2014
DOI:https://doi.org/10.1103/PhysRevB.91.014430
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