Multiferroic tunnel junctions

Magnetic tunnel junctions with ferroelectric barriers, often referred to as multiferroic tunnel junctions, have been proposed recently to display new functionalities and new device concepts. One of the notable predictions is that the combination of two charge polarizing states and the parallel and antiparallel magnetic states could make it a four resistance state device. We have recently studied the ferroelectric tunneling using a scanning probe technique and multiferroic tunnel junctions using ferromagnetic La 0.7 Ca 0.3 MnO 3 and La 0.7 Sr 0.3 MnO 3 as the electrodes and ferroelectric (Ba, Sr)TiO 3 as the barrier in trilayer planner junctions. We show that very thin (Ba, Sr)TiO 3 films can sustain ferroelectricity up till room temperature. The multiferroic tunnel junctions show four resistance states as predicted and can operate at room temperatures.