M. Jamet

Spin pumping and inverse spin Hall effect in germanium

We have measured the inverse spin Hall effect (ISHE) in

Strain and correlation of self-organized Ge1 xMnx nanocolumns embedded in Ge (001)

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Investigation of magnetic anisotropy of (Ge,Mn) nanocolumns

-Ge at room temperature. The spin current in germanium was generated by spin pumping from a CoFeB/MgO magnetic tunnel junction in order to prevent the impedance mismatch issue. A clear electromotive force was measured in Ge at the ferromagnetic resonance of CoFeB. The same study was then carried out on several test samples, in particular, we have investigated the influence of the MgO tunnel barrier and sample annealing on the ISHE signal. First, the reference CoFeB/MgO bilayer grown on SiO

Spin transport in p-type germanium

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Structure and magnetism of Ge3Mn5 clusters

exhibits a clear electromotive force due to anisotropic magnetoresistance and anomalous Hall effect, which is dominated by an asymmetric contribution with respect to the resonance field. We also found that the MgO tunnel barrier is essential to observe ISHE in Ge and that sample annealing systematically leads to an increase of the signal. We propose a theoretical model based on the presence of localized states at the interface between the MgO tunnel barrier and Ge to account for these observations. Finally, all of our results are fully consistent with the observation of ISHE in heavily doped

Atomic structure of Mn-rich nanocolumns probed by x-ray absorption spectroscopy

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Millimeter-scale layered MoSe2 grown on sapphire and evidence for negative magnetoresistance

-Ge and we could estimate the spin Hall angle at room temperature to be

In-plane and out-of-plane spin precession in lateral spin-valves

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Spin-Hall Voltage over a Large Length Scale in Bulk Germanium

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Switchable spin-current source controlled by magnetic domain walls.

We report on the structural properties of Ge_(1-x)Mn_x layers grown by molecular beam epitaxy. In these layers, nanocolumns with a high Mn content are embedded in an almost-pure Ge matrix. We have used grazing-incidence X-ray scattering, atomic force and transmission electron microscopy to study the structural properties of the columns. We demonstrate how the elastic deformation of the matrix (as calculated using atomistic simulations) around the columns, as well as the average inter-column distance can account for the shape of the diffusion around Bragg peaks.