With the general objective of studying interfaces between ferromagnetic materials and organic semiconductors, we report ac impedance investigations on La0.7Sr0.3MnO3 (LSMO)/tris(8-hydroxyquinoline)aluminium (Alq3)/Al and Indium Tin Oxide (ITO)/Alq3/Al heterostructures, in the frequency range between 20 Hz and 1 MHz. The comparison of the equivalent circuits deduced to fit the experimental ac responses allows isolating a specific RC contribution which can be attributed to the LSMO/Alq3 interface region. Using the information obtained from our ac measurements, we propose a model which fits the temperature dependence of the magnetoresistance in spin valves combining LSMO electrodes and Alq3 layers. (C) 2008 Elsevier B.V. All rights reserved.
Manganite/Alq3 interfaces investigated by impedance spectroscopy technique
Barra M;Cassinese A;D'Angelo P;Graziosi P;Dediu V
2008
Abstract
With the general objective of studying interfaces between ferromagnetic materials and organic semiconductors, we report ac impedance investigations on La0.7Sr0.3MnO3 (LSMO)/tris(8-hydroxyquinoline)aluminium (Alq3)/Al and Indium Tin Oxide (ITO)/Alq3/Al heterostructures, in the frequency range between 20 Hz and 1 MHz. The comparison of the equivalent circuits deduced to fit the experimental ac responses allows isolating a specific RC contribution which can be attributed to the LSMO/Alq3 interface region. Using the information obtained from our ac measurements, we propose a model which fits the temperature dependence of the magnetoresistance in spin valves combining LSMO electrodes and Alq3 layers. (C) 2008 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.