BiFeO3 is a one of the very few room-temperature multiferroic materials [1]. Its rediscovery fourteen years ago was initially motivated by a possible application in electric-field controlled spintronics devices. Other important properties of BiFeO3 are its remarkable spontaneous polarization of 100 µC/cm² in the <111> pseudocubic direction, high Curie temperature of 1100 K and cycloidal spin order in the bulk. In addition, BiFeO3 possesses interesting optical characteristics, such as a band gap in the visible range (2.7 eV) and a large birefringence.
In this talk, I will first describe how BiFeO3's structural, ferroelectric, magnetic and optical properties can be tuned by epitaxial strain, thereby unveiling novel functionalities of interest for applications in various fields. I will then focus on the electric-field control of magnetism, in micronic devices and at the nanoscale. Finally, I will show how BiFeO3 can be integrated as a barrier in ferroelectric tunnel junctions showing a memristive response [3], with potential for neuromorphic computational architectures [4].
[1] D. Sando, A. Barthelemy, and M. Bibes, J. Phys. Condens. Matter 26, 473201 (2014).
[2] D. Sando et al, Nature Mater. 12, 641 (2013).
[3] A. Chanthbouala et al, Nature Mater. 11, 860 (2012).
[9] S. Boyn et al, Nature Commun. 8, 14736 (2017)