title: Disorder-induced room temperature ferromagnetism in glassy chromites.
abstract: We report an unusual robust ferromagnetic order above room temperature upon amorphization of perovskite [YCrO3] in pulsed laser deposited thin films. This is contrary to the usual expected formation of a spin glass magnetic state in the resulting disordered structure. To understand the underlying physics of this phenomenon, we combine advanced spectroscopic techniques and first-principles calculations. We find that the observed order-disorder transformation is accompanied by an insulator-metal transition arising from a wide distribution of Cr-O-Cr bond angles and the consequent metallization through free carriers. Similar results also found in YbCrO3-films suggest that the observed phenomenon is more general and should, in principle, apply to a wider range of oxide systems. The ability to tailor ferromagnetic order above room temperature in oxide materials opens up many possibilities for novel technological applications of this counter intuitive effect.
authors.affiliation: Condensed Matter Theory Group, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120, Uppsala, Sweden.
authors.forename: C Moyses
authors.initials: CM
authors.lastname: Araujo
authors.affiliation: Department of Materials Science, Tmfy-MSE, Royal Institute of Technology, SE100 44 Stockholm, Sweden.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Nagar
authors.affiliation: Condensed Matter Theory Group, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120, Uppsala, Sweden.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Ramzan
authors.affiliation: Solid State Chemistry Section, Chemistry Division, Bhabha Atomic Research Centre, Mumbai, 400085 India.
authors.forename: R
authors.initials: R
authors.lastname: Shukla
authors.affiliation: Solid State Chemistry Section, Chemistry Division, Bhabha Atomic Research Centre, Mumbai, 400085 India.
authors.forename: O D
authors.initials: OD
authors.lastname: Jayakumar
authors.affiliation: Solid State Chemistry Section, Chemistry Division, Bhabha Atomic Research Centre, Mumbai, 400085 India.
authors.forename: A K
authors.initials: AK
authors.lastname: Tyagi
authors.affiliation: 1] Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley CA94720, USA [2] Department of Physics, Tamkang University, Tamsui, Taiwan 250, R.O.C.
authors.forename: Yi-Sheng
authors.initials: YS
authors.lastname: Liu
authors.affiliation: 1] Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley CA94720, USA [2] Department of Physics, Tamkang University, Tamsui, Taiwan 250, R.O.C.
authors.forename: Jeng-Lung
authors.initials: JL
authors.lastname: Chen
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley CA94720, USA.
authors.forename: Per-Anders
authors.initials: PA
authors.lastname: Glans
authors.affiliation: Department of Physics, Tamkang University, Tamsui, Taiwan 250, R.O.C.
authors.forename: Chinglin
authors.initials: C
authors.lastname: Chang
authors.affiliation: Condensed Matter Theory Group, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120, Uppsala, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Blomqvist
authors.affiliation: Instituto de Ciencias Físicas y Matemáticas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
authors.forename: Raquel
authors.initials: R
authors.lastname: Lizárraga
authors.affiliation: Instituto de Ciencias Físicas y Matemáticas, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
authors.forename: Erik
authors.initials: E
authors.lastname: Holmström
authors.affiliation: Department of Materials Science, Tmfy-MSE, Royal Institute of Technology, SE100 44 Stockholm, Sweden.
authors.forename: Lyubov
authors.initials: L
authors.lastname: Belova
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley CA94720, USA.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Guo
authors.affiliation: 1] Condensed Matter Theory Group, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120, Uppsala, Sweden [2] Applied Materials Physics, Department of Materials and Engineering, Royal Institute of Technology (KTH), SE-100 44 Stockholm, Sweden.
authors.forename: Rajeev
authors.initials: R
authors.lastname: Ahuja
authors.affiliation: Department of Materials Science, Tmfy-MSE, Royal Institute of Technology, SE100 44 Stockholm, Sweden.
authors.forename: K V
authors.initials: KV
authors.lastname: Rao
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