2009/06/18 by J. D. Burton, J. P. Velev, Julian Velev +2
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Chemistry #Condensed matter physics #Electron #Electronic and Structural Properties of Oxides #Fermi gas #Heterojunction #Magnetic and transport properties of perovskites and related materials #Materials science #Nanoelectronics #Nanotechnology #Oxide #Physics #Polarization (electrochemistry) #Quantum mechanics #Quantum tunnelling #Semiconductor materials and devices #Tunnel junction #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.80.115408
published as Physical Review B, 80 115408 (2009). · 8 pages, 5 figures, 1 table
arxiv created 2009/06/18 · openalex publication_date 2009/09/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The discovery of a two-dimensional electron gas (2DEG) at the interface between insulating oxides has led to a well-deserved level of excitement due to possible applications as ``in-plane'' all-oxide nanoelectronics. Here we expand the range of possibilities to the realm of ``out-of-plane'' nanoelectronics by examining such all-oxide heterostructures as barriers in tunnel junctions. As an example system we perform first-principles electronic structure and transport calculations of a tunnel junction with a [SrTiO3]4/[LaO]1/[SrTiO3]4 heterostructure tunneling barrier embedded between SrRuO3 electrodes. The presence of the LaO atomic layer induces the formation of a 2DEG within the tunneling barrier which acts as an extended 2D potential well perpendicular to the transport direction, providing a route for resonant tunneling. Our calculations demonstrate that the tunneling conductance in this system can be strongly enhanced compared to a pure SrTiO3 barrier due to resonant tunneling, but that lattice polarization effects play a significant role in determining this behavior. In addition we find that this resonant tunneling is highly selective of the orbital symmetry of the tunneling states due to the ``orbital polarization'' of the 2DEG. We also discuss how the properties of the 2DEG are affected by the presence of metal electrodes.