1305.3990 (Y. M. Sheu et al.)

Polaronic nature of competing interfacial
ferromagnetic/antiferromagnetic order in La(0.7)Ca(0.3)MnO(3)/BiFeO(3)
heterostructure    [PDF]

Y. M. Sheu, S. A. Trugman, L. Yan, J. Qi, Q. X. Jia, A. J. Taylor, R. P. Prasankumar

Using ultrafast optical spectroscopy, we show that polaronic behavior associated with interfacial antiferromagnetic order is the origin of tunable magnetotranport upon switching the ferroelectric polarity in a La$_{0.7}$Ca$_{0.3}$MnO$_{3}$/BiFeO$_{3}$ (LCMO/BFO) heterostructure. This is revealed through the difference in dynamical spectral weight transfer (DSWT) between LCMO and LCMO/BFO at low temperatures, which can be linked to polaronic transport in LCMO/BFO. This polaronic feature in LCMO/BFO decreases in relatively high magnetic fields, while no discernible change is found in the LCMO film at low temperatures. These results thus shed new light on the intrinsic mechanisms governing magnetoelectric coupling in this heterostructure.

View original: http://arxiv.org/abs/1305.3990