title: Formation and Observation of a Quasi-Two-Dimensional dxy Electron Liquid in Epitaxially Stabilized Sr(2-x)La(x)TiO4 Thin Films.
abstract: We report the formation and observation of an electron liquid in Sr(2-x)La(x)TiO4, the quasi-two-dimensional counterpart of SrTiO3, through reactive molecular-beam epitaxy and in situ angle-resolved photoemission spectroscopy. The lowest lying states are found to be comprised of Ti 3d_{xy} orbitals, analogous to the LaAlO3/SrTiO3 interface and exhibit unusually broad features characterized by quantized energy levels and a reduced Luttinger volume. Using model calculations, we explain these characteristics through an interplay of disorder and electron-phonon coupling acting cooperatively at similar energy scales, which provides a possible mechanism for explaining the low free carrier concentrations observed at various oxide heterostructures such as the LaAlO3/SrTiO3 interface.
authors.affiliation: National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, People's Republic of China.|Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.|Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Y F
authors.initials: YF
authors.lastname: Nie
authors.affiliation: Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, Coppito, L'Aquila I-67100, Italy.|CNR-SPIN, Via Vetoio, L'Aquila I-67100, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Di Sante
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: S
authors.initials: S
authors.lastname: Chatterjee
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.|Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors.forename: P D C
authors.initials: PD
authors.lastname: King
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: M
authors.initials: M
authors.lastname: Uchida
authors.affiliation: Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, Coppito, L'Aquila I-67100, Italy.|CNR-ISC, Via dei Taurini, Rome I-00185, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Ciuchi
authors.affiliation: Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.|Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors.forename: D G
authors.initials: DG
authors.lastname: Schlom
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.|Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Shen