Fig. 1: Design of double-cross device for differential voltage measurements.
a Microscope image of one of the studied devices. The device consists of two crosses with the same dimensions, where one has an IrMn3 pillar and the second consists only of Pt. The electrodes are labeled from 1 to 6 to specify the directions in which the write current pulses are applied (Ii-jwrite refers to the write current applied between electrodes i and j). In all cases, the electrodes 2 and 3 are used for measuring the differential readout voltage, V2-3read, while applying a small reading current, 100 µA, between electrodes 1 and 4. b Schematic representation of the device, showing the current sources (Iwrite and Iread) and the nanovoltmeter (V) connections for one of the switching experiments (I2-6write). The other measurement configurations used in this study are outlined in the main text. The Cartesian coordinate system used here is also indicated as an inset.
