title: Condensation of two-dimensional oxide-interfacial charges into one-dimensional electron chains by the misfit-dislocation strain field.
abstract: The success of semiconductor technology is largely ascribed to controlled impacts of strains and defects on the two-dimensional interfacial charges. Interfacial charges also appear in oxide heterojunctions such as LaAlO3/SrTiO3 and (Nd0.35Sr0.65)MnO3/SrTiO3. How the localized strain field of one-dimensional misfit dislocations, defects resulting from the intrinsic misfit strains, would affect the extended oxide-interfacial charges is intriguing and remains unresolved. Here we show the atomic-scale observation of one-dimensional electron chains formed in (Nd0.35Sr0.65)MnO3/SrTiO3 by the condensation of characteristic two-dimensional interfacial charges into the strain field of periodically arrayed misfit dislocations, using chemical mapping and quantification by scanning transmission electron microscopy. The strain-relaxed inter-dislocation regions are readily charge depleted, otherwise decorated by the pristine charges, and the corresponding total-energy calculations unravel the undocumented charge-reservoir role played by the dislocation-strain field. This two-dimensional-to-one-dimensional electronic condensation represents a novel electronic-inhomogeneity mechanism at oxide interfaces and could stimulate further studies of one-dimensional electron density in oxide heterostructures.
authors.affiliation: 1] Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan [2] Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan.
authors.forename: C-P
authors.initials: CP
authors.lastname: Chang
authors.affiliation: 1] Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan [2] Taiwan Consortium of Emergent Crystalline Materials, Ministry of Science and Technology, Taipei 106, Taiwan.
authors.forename: M-W
authors.initials: MW
authors.lastname: Chu
authors.affiliation: 1] Department of Physics, National Tsing Hua University, Hsinchu 300, Taiwan [2] Institute of Physics, Academia Sinica, Taipei 115, Taiwan.
authors.forename: H T
authors.initials: HT
authors.lastname: Jeng
authors.affiliation: 1] Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan [2] Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan.
authors.forename: S-L
authors.initials: SL
authors.lastname: Cheng
authors.affiliation: Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan.
authors.forename: J G
authors.initials: JG
authors.lastname: Lin
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, Taipei 106, Taiwan.
authors.forename: J-R
authors.initials: JR
authors.lastname: Yang
authors.affiliation: Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan.
authors.forename: C H
authors.initials: CH
authors.lastname: Chen