Enhanced conduction and ferromagnetic order at (100)-type twin walls in La0.7 Sr0.3MnO3 thin films

Under the terms of the Creative Commons Attribution License 3.0 (CC-BY).There is increasing evidence supporting the strong potential of twin walls in ferroic materials as distinct, spatially tunable, functional elements in future electronic devices. Here, we report an increase of about one order of magnitude in conductivity and more robust magnetic interactions at (100)-type twin walls in La0.7Sr0.3MnO3 thin films. The nature and microscopic origin of such distinctive behavior is investigated by combining conductive, magnetic, and force modulation scanning force microscopies with transmission electron microscopy techniques. Our analyses indicate that the observed behavior is due to a severe compressive strained state within an ∼1nm slab of material centered at the twin walls, promoting stronger Mn 3d-O2p orbital overlapping leading to a broader bandwidth and enhanced magnetic interactions.This research was sponsored by the Spanish MINECO (Grants No. MAT2011- 29081-C02, No. MAT2012-33207, and No. MAT2013-47869-C4-1-P) projects. We also acknowledge financial aid from the Generalitat de Catalunya (2014 SGR 501). N.B. and F.S. also acknowledge funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483-ESTEEM2 (Integrated Infrastructure Initiative I3) for providing access to aberration corrected electron microscopes at CEMES (Toulouse) and LPS (Orsay). R.G. and N.B. thank the Spanish MINECO for financial support through the FPI program. F.S. acknowledges support from the Labex (Excellence Laboratory) NEXT through a visiting scientist fellowship at CEMES (Toulouse, France).Peer Reviewe