(a) Schematic diagram of the four resistance states in artificial MFTJS with two FM electrodes sandwiching an FE tunnel barrier. The white and black arrows represent the magnetic configurations and FE polarization, respectively. (b) Tunnel magnetoresistance curves at 4 K with V_dc. = 10 mV in an LSMO (x = 0.33)/LBMO(2 nm)/Au junction.^[94] (c) Resistance versus magnetic field (R–H) curves for LSMO (x = 0.33)/BTO (1 nm)/Fe MFTJ (V_dc. = −50 mV, T = 4.2 K) after poling the ferroelectric barrier up or down, respectively.^[95] (d) R–H curves measured at 50 K in the as-grown state of LSMO (x = 0.33)/PZT (3.2 nm)/Fe MFTJ.^[96] (e) R–H curves for LSMO (x = 0.3)/LCMO (x = 0.5)/BTO/LSMO (x = 0.3) MFTJ.^[97]