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Title: Interface Engineered Room‐Temperature Ferromagnetic Insulating State in Ultrathin Manganite Films
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 La0.9Ba0.1MnO3films grown on SrTiO3substrates via an interface proximity effect. Detailed scanning transmission electron microscopy images clearly demonstrate that MnO6octahedral rotations in La0.9Ba0.1MnO3close to the interface are strongly suppressed. As determined from in situ X‐ray photoemission spectroscopy, OK‐edge X‐ray absorption spectroscopy, and density functional theory, the realization of the FMI state arises from a reduction of Mn egbandwidth caused by the quenched MnO6octahedral rotations. The emerging FMI state in La0.9Ba0.1MnO3together with necessary coherent interface achieved with the perovskite substrate gives very high potential for future high performance electronic devices.

 
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Award ID(s):
1809520
NSF-PAR ID:
10458614
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Science
Volume:
7
Issue:
1
ISSN:
2198-3844
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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