Continuously-tuned tunneling behaviors of ferroelectric tunnel junctions based on BaTiO3/La0.67Sr0.33MnO3 heterostructure

In this work, we fabricate BaTiO3/La0.67Sr0.33MnO3 (BTO/LSMO) ferroelectric tunnel junction on (001) SrTiO3 substrate by pulsed laser deposition method. Combining piezoresponse force and conductive-tip atomic force microscopy, we demonstrate robust and reproducible polarization-controlled tunneling behaviors with the resulting tunneling electroresistance value reaching about 102 in ultrathin BTO films (∼1.2 nm) at room temperature. Moreover, local poling areas with different conductivity are finally achieved by controlling the relative proportion of upward and downward domains, and different poling areas exhibit stable transport properties.