Polarons and confinement of electronic motion to two dimensions in a layered transition metal oxide

Abstract

A very remarkable feature of the layered transition metal oxides (TMOs), whose most famous members are the high-temperature superconductors (HTSs), is that even though they are prepared as bulk three-dimensional single crystals, they display hugely anisotropic electrical and optical properties, seeming to be insulating perpendicular to the layers and metallic within them. This is the phenomenon of confinement, a concept at odds with the conventional theory of solids and recognized as due to magnetic and electron-lattice interactions in the layers which must be overcome at a substantial energy cost if electrons are to be transferred between layers. The associated energy gap or 'pseudogap' is particularly obvious in experiments where charge is moved perpendicular to the planes, most notably scanning tunneling microscopy (STM) and polarized infrared spectroscopy. Here, using the same experimental tools, we show that there is a second family of TMOs - the layered manganites La2-2xSr1+2xMn2O7 (LSMO) - with even more extreme confinement and pseudogap effects. The data, which are the first to resolve atoms in any metallic manganite, demonstrate quantitatively that because they are attached to polarons - lattice and spin textures within the planes -, it is equally difficult to remove carriers from the planes via vacuum tunneling into a conventional metallic tip, as it is for them to move between Mn-rich layers within the material itself.

References in corpus (8)

• Imaging Quasiparticle Interference in Bi2Sr2CaCu2O8+d
• Nodal quasiparticle in pseudogapped colossal magnetoresistive manganites
• Atomic-scale images of charge ordering in a mixed-valence manganite
• Impurity-Induced Bound Excitations on the Surface of Bi2Sr2CaCu2O8
• Intrinsic Inhomogeneities in Manganite Thin Films Investigated with Scanning Tunneling Spectroscopy
• An ordered stack of spin valves in a layered magnetoresistive perovskite
• Full Bulk Spin Polarization and Intrinsic Tunnel Barriers at the Surface of Layered Manganites
• The Structure of Nanoscale Polaron Correlations in La1.2Sr1.8Mn2O7

Cited by in corpus (34)

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• Magnetic order induced crystal symmetry lowering in ACr${}_2$O${}_4$ ferrimagnetic spinels
• Many-body large polaron optical conductivity in SrTi${}_{1-x}$Nb${}_x$O${}_3$
• Spatially Resolved Mapping of Local Polarization Dynamics in an Ergodic Phase of Ferroelectric Relaxor
• Lattice potentials and fermions in holographic non Fermi-liquids: hybridizing local quantum criticality
• Imaging Oxygen Defects and their Motion at a Manganite Surface
• Electronic phase separation: recent progress in the old problem
• Bilayer manganites: polarons in the midst of a metallic breakdown
• Quantum simulation of electron-phonon interactions in strongly deformable materials
• Suppressed Magnetization at the Surfaces and Interfaces of Ferromagnetic Metallic Manganites
• Atomic-scale Manipulation of Single-Polaron in a Two-Dimensional Semiconductor
• Small Polarons in Transition Metal Oxides
• Manipulating single excess electrons in monolayer transition metal dihalide
• Stripe charge ordering in SrO-terminated SrTiO3(001) surfaces
• Polaronic signature in the metallic phase of La0.7Ca0.3MnO3 films detected by scanning tunneling spectroscopy
• Small-scale phase separation in doped anisotropic antiferromagnets
• Direct imaging of lattice strain-induced stripe phases in an optimally-doped manganite
• Non-gapped Fermi surfaces, quasiparticles and the anomalous temperature dependence of the near-$E_F$ electronic states in the CMR oxide La${}_{2-2x}$Sr${}_{1+2x}$Mn${}_2$O${}_7$ with $x=0.36$
• Isotropic Kink and Quasiparticle Excitations in the Three-Dimensional Perovskite Manganite La${}_{0.6}$Sr${}_{0.4}$MnO${}_3$
• Tunneling Study of the Charge-Ordering Gap on the Surface of La${}_{0.350}$Pr${}_{0.275}$Ca${}_{0.375}$MnO${}_3$ Thin Films
• Structural and magnetic characterization of the elusive Jahn-Teller active NaCrF3
• Etching of Cr tips for scanning tunneling microscopy of cleavable oxides
• A high resolution, hard x-ray photoemission investigation of La_(2-2x)Sr_(1+2x)Mn_2O_7 (0.30<x<0.50): on microscopic phase separation and the surface electronic structure of a bilayered CMR manganite
• Orbital Selective Directional Conductor in the Two Orbital Hubbard Model
• Bilayer splitting and c-axis coupling in bilayer manganites showing colossal magnetoresistance
• An STM perspective on hexaborides: Surface states of the Kondo insulator SmB${}_6$
• Temperature and Field Dependence of Magnetic Domains in La${}_{1.2}$Sr${}_{1.8}$Mn${}_2$O${}_7$
• Observation of electronic inhomogeneity and charge density wave in a bilayer La${}_{1.36}$Sr${}_{1.64}$Mn${}_2$O${}_7$ single crystal
• Fingerprint of dynamical charge/spin correlations in the tunneling spectra of colossal magnetoresistive manganites
• Evidence of mobile carriers with Charge Ordering gap in Epitaxial Pr${}_{0.625}$Ca${}_{0.375}$MnO${}_3$ Thin Films
• Predictability as a probe of manifest and latent physics: The case of atomic scale structural, chemical, and polarization behaviors in multiferroic Sm-doped BiFeO3