Analysis of the magnetotransport channels in tunnel junctions with amorphousT. Dimopoulos1, G. Gieres1, J. Wecker1, Y. Luo2 and K. Samwer2
1 Siemens AG, Corporate Technology CT-MM1 Paul-Gossen-Str. 100, 91052, Erlangen, Germany
2 I. Physikalisches Institut, University of Göttingen Tammannstr. 1, 37077, Göttingen, Germany
received 1 June 2004; accepted in final form 12 October 2004
published online 5 November 2004
This work concerns the temperature and bias dependence of the magnetotransport properties of oxide-based tunnel junctions with an amorphous soft ferromagnetic electrode and -based polycrystalline hard electrode. The junctions present high tunnel magnetoresistance of % at room temperature and % at 5 . A model that takes magnon-assisted inelastic tunneling into account fits satisfactorily the parallel (P) and antiparallel (AP) conductance as a function of temperature. The extracted fitting parameters are then used to reproduce the low-bias anomaly of the P and AP conductance at low temperature.
73.40.Gk - Tunneling.
73.40.Rw - Metal-insulator-metal structures.
75.47.De - Giant magnetoresistance.
© EDP Sciences 2004