Superconducting gap induced barrier enhancement in a BiFeO3-based heterostructure

Authors: C. L. Lu, Y. Wang, L. You, X. Zhou, H. Y. Peng, G. Z. Xing, E. E. M. Chia, C. Panagopoulos, L. Chen, J.-M. Liu, J. Wang, and T. Wu

Published in: Applied Physics Letters 97, 252905, 2010.

We report the synthesis and characterization of an epitaxial heterostructure composed of multi- ferroic BiFeO3 and superconducting YBa2Cu3O7-δ thin films grown on 001 SrTiO3. Both the superconductivity of YBa2Cu3O7-δ and the ferroelectricity of BiFeO3 are retained in the heterostructure. Current density-electric field characteristics measured from 30 to 170 K suggest a Schottky-emission-like transport at the BiFeO3/YBa2Cu3O7-δ interface. Furthermore, the temperature dependence of the barrier height shows an anomalous enhancement at TC, indicating an intimate coupling between the multiferroic and the superconducting layers.

DOI: 10.1063/1.3530446