Interface engineered room‐temperature ferromagnetic insulating state in ultrathin manganite films

DOI: 10.1002/advs.201901606

Authors: Weiwei Li (University of Cambridge) , Bonan Zhu (University of Cambridge) , Qian He (Cardiff University) , Albina Y. Borisevich (Oak Ridge National Laboratory) , Chao Yun (University of Cambridge) , Rui Wu (University of Cambridge) , Ping Lu (Sandia National Laboratory) , Zhimin Qi (Purdue University) , Qiang Wang (West Virginia University) , Aiping Chen (Los Alamos National Laboratory) , Haiyan Wang (Purdue University) , Stuart A. Cavill (University of York; Diamond Light Source) , Kelvin H. L. Zhang (Xiamen University) , Judith L. Macmanus‐driscoll (University of Cambridge)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Advanced Science , VOL 5

State: Published (Approved)
Published: November 2019
Diamond Proposal Number(s): 17284

Abstract: Ultrathin epitaxial films of ferromagnetic insulators (FMIs) with Curie temperatures near room temperature are critically needed for use in dissipationless quantum computation and spintronic devices. However, such materials are extremely rare. Here, a room‐temperature FMI is achieved in ultrathin La0.9Ba0.1MnO3 films grown on SrTiO3 substrates via an interface proximity effect. Detailed scanning transmission electron microscopy images clearly demonstrate that MnO6 octahedral rotations in La0.9Ba0.1MnO3 close to the interface are strongly suppressed. As determined from in situ X‐ray photoemission spectroscopy, O K‐edge X‐ray absorption spectroscopy, and density functional theory, the realization of the FMI state arises from a reduction of Mn eg bandwidth caused by the quenched MnO6 octahedral rotations. The emerging FMI state in La0.9Ba0.1MnO3 together with necessary coherent interface achieved with the perovskite substrate gives very high potential for future high performance electronic devices.

Journal Keywords: ABO3 perovskite oxides; ferromagnetic insulators; interface engineering; manganite thin films; octahedral proximity effect

Diamond Keywords: Ferromagnetism

Subject Areas: Materials, Physics


Instruments: I06-Nanoscience

Added On: 19/11/2019 11:32

Documents:
Li_et_al-2019.pdf

Discipline Tags:

Surfaces Quantum Materials Physics Electronics Magnetism Materials Science interfaces and thin films Perovskites Metallurgy

Technical Tags:

Spectroscopy X-ray Absorption Spectroscopy (XAS)