Interface-Modification-Enhanced Tunnel Electroresistance In Multiferroic Tunnel Junctions

We report a large tunnel electroresistance (TER) effect up to similar to 10(4)% in La0.67Sr0.33MnO3/BaTiO3/Co (LSMO/BTO/Co) multiferroic tunnel junctions (MFTJs), which couples with well-defined tunnel magnetoresistance. The large TER is related to (LaAlO3)(0.3)(LaSrTaO6)(0.7) substrates which guarantee a high-quality LSMO/BTO interface and robust ferroelectricity in BTO. The insert of 0.5 nm-thick Pt between the Co electrode and BTO barrier further enhances the TER value to 10(5)% and improves the endurance of the MFTJs, ascribed to the shortened screening length and reduced oxidation of BTO/Co interface. Their use would advance the process towards practical MFTJs with four resistance states. (C) 2014 AIP Publishing LLC.