title: Long-range electronic reconstruction to a dxz,yz-dominated Fermi surface below the LaAlO₃/SrTiO₃ interface.
abstract: Low dimensionality, broken symmetry and easily-modulated carrier concentrations provoke novel electronic phase emergence at oxide interfaces. However, the spatial extent of such reconstructions - i.e. the interfacial "depth" - remains unclear. Examining LaAlO₃/SrTiO₃ heterostructures at previously unexplored carrier densities n(2D) ≥ 6.9 × 10(14) cm(-2), we observe a Shubnikov-de Haas effect for small in-plane fields, characteristic of an anisotropic 3D Fermi surface with preferential dxz,yz orbital occupancy extending over at least 100 nm perpendicular to the interface. Quantum oscillations from the 3D Fermi surface of bulk doped SrTiO₃ emerge simultaneously at higher n(2D). We distinguish three areas in doped perovskite heterostructures: narrow (<20 nm) 2D interfaces housing superconductivity and/or other emergent phases, electronically isotropic regions far (>120 nm) from the interface and new intermediate zones where interfacial proximity renormalises the electronic structure relative to the bulk.
authors.affiliation: School of Physical and Mathematical Sciences, Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore.
authors.forename: A P
authors.initials: AP
authors.lastname: Petrović
authors.affiliation: School of Physical and Mathematical Sciences, Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Paré
authors.affiliation: Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska Lincoln, Nebraska 68588-0299, USA.
authors.forename: T R
authors.initials: TR
authors.lastname: Paudel
authors.affiliation: 1] School of Physical and Mathematical Sciences, Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore [2] Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: K
authors.initials: K
authors.lastname: Lee
authors.affiliation: Toshiba Research Europe Ltd., Cambridge Research Laboratory, 208 Cambridge Science Park, Milton Road, Cambridge CB4 0GZ, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Holmes
authors.affiliation: Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: C H W
authors.initials: CH
authors.lastname: Barnes
authors.affiliation: School of Physical and Mathematical Sciences, Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore.
authors.forename: A
authors.initials: A
authors.lastname: David
authors.affiliation: School of Physical and Mathematical Sciences, Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore.
authors.forename: T
authors.initials: T
authors.lastname: Wu
authors.affiliation: Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska Lincoln, Nebraska 68588-0299, USA.
authors.forename: E Y
authors.initials: EY
authors.lastname: Tsymbal
authors.affiliation: 1] School of Physical and Mathematical Sciences, Division of Physics and Applied Physics, Nanyang Technological University, 637371 Singapore [2] Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Panagopoulos