Atomic-scale electronic reconstruction at the BiFeO3/La0.7Sr0.3MnO3 heterointerfaces
Bo-Chao Huang1,2,3*, Pu Yu4,5, Chia-SengChang1, Ying-Hao Chu1,5,7, Ya-Ping Chiu2,1,3,7
1Institute of Physics, Academia Sinica, Taipei, Taiwan
2Department of Physics, National Taiwan Normal University, Taipei, Taiwan
3Department of Physics, National Sun Yat-sen University, Kaohsiung, Taiwan
4State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, and Collaborative Innovation Center of Quantum Matter, Beijing, China
5Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan
6RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, Japan
7Taiwan Consortium of Emergent Crystalline Materials (TCECM), Ministry of Science and Technology, Taipei, Taiwan
* presenting author:Bo-Chao Huang,
An atomic-level band mapping across engineered BiFeO3/La0.7Sr0.3MnO3 heterointerfaces was realized using cross-sectional scanning tunneling microscopy and spectroscopy. The evolution of the electronic structures suggests that the interface-dipole and therefore the ferroelectric polarization in the BiFeO3 layer are switchable by simply manipulating the termination at the interface. Furthermore, atomic-level spectroscopic results indicate that the change of band structures across the hetoerinterface is correlated with the orbital coupling between BiFeO3 and La0.7Sr0.3MnO3. This work provides deep insights into the electronic structure across oxide heterointerfaces, which is crucial to understand and design a host of novel functionalities using the emergent states at complex oxide heterointerfaces.

Keywords: cross-sectional STM, BFO/LSMO, interface, electronic reconstruction, multiferroic