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arXiv · 1211.0489

Interface characterization of Co2MnGe/Rh2CuSn Heusler multilayers

Ronny Knut·Peter Svedlindh·Klas Gunnarsson·Oleg Mryasov·Peter Warnicke·Dario Arena·Matts Björck·D. D. Sarma·Anindita Sahoo·Sumanta Mukherjee·Sari Granroth·Mihaela Gorgoi·Olof Karis
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Abstract

All-Heusler multilayer structures have been investigated by means of high kinetic x-ray photoelectron spectroscopy and x-ray magnetic circular dichroism, aiming to address the amount of disorder and interface diffusion induced by annealing of the multilayer structure. The studied multilayers consist of ferromagnetic Co$_2$MnGe and non-magnetic Rh$_2$CuSn layers with varying thicknesses. We find that diffusion begins already at comparably low temperatures between 200 $^{\circ}$C and 250 $^{\circ}$C, where Mn appears to be most prone to diffusion. We also find evidence for a 4 Å thick magnetically dead layer that, together with the identified interlayer diffusion, are likely reasons for the small magnetoresistance found for current-perpendicular-to-plane giant magneto-resistance devices based on this all-Heusler system.

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Ronny Knut, Peter Svedlindh, Klas Gunnarsson, Oleg Mryasov, Peter Warnicke, Dario Arena, Matts Björck, D. D. Sarma, Anindita Sahoo, Sumanta Mukherjee, Sari Granroth, Mihaela Gorgoi, Olof Karis. 2013-01-25. Interface characterization of Co2MnGe/Rh2CuSn Heusler multilayers. https://doi.org/10.1103/physrevb.88.134407

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