B9: Spin pumping and spin transfer at magnetic oxide interfaces
Spin pumping and spin transfer torque are phenomena which have mainly been investigated in metalic systems. Here we will study these effects in ferromagnetic oxides which exhibit an increased spin polarization yielding the promise of larger effects and higher efficiency.
Furthermore the large crystalline anisotropies in magnetic oxides provide additional degrees of freedom for the experiment compared to metallic layers. In the beginning of the project the effect of spin pumping will be demonstrated by means of ferrmagnetic resonance (FMR) of oxide films. The experiments will investigate the coupling between ferromagnetic oxide thin films which are separated by thin non-magnetic films which can either be conducting or insulating (for example lanthanum strontium manganite/ strontium titanate / strontium ruthenate). Here especially those oxides are interesting which have a Curie temperature below room temperature. As the FMR experiments can also be perfomred at low temperatures, temperature can be an additional lever tto control magnetization and anisotropy, facilitating the tuning of resonance frequencies which is necessary to achieve synchronization of two layers.
In the following parts of the project the investigations are expanded towards spin tranfer torque in ferromagnetic oxide/metal hybrid nanostructures. Beyond these studies the project will also investigate the change of anisotropy in artificial layered multiferroics under applied bias. These multiferroics will be supplied by other projects. For these experiments the FMR setup will be modified to allow for FMR studies while a DC voltage is applied to the sample.
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Prof. Dr. Georg Schmidt ⇒
georg.schmidt@physik.uni-halle.de phone: +49 (0) 345/55 25320 fax: +49 (0) 345/55 27034 |
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