Reversible change of magnetism in FePt films by electrochemical charging in a LiClO_4 based electrolyte

摘要

Electric field induced changes of magnetic properties are of great interest to magnetic data storage and multifunctional micro- and nanoscaled devices. At the electrode/electrolyte interface various processes allow to change the magnetic properties at the electrode surface by an external voltage. The electrode processes at FePt thin films are investigated for different electrolytes. In LiPF_6 based electrolytes, irreversible chemical reactions occur due to the presence of HF. When LiClO_4 is used instead, the FePt/Fe-O film remains unchanged during immersion. During charging, as for LiPF_6, the magnetization of FePt thin films can be changed by exploiting oxidation/reduction mechanisms in a naturally grown metal oxide layer.