title: Controlling band alignments by artificial interface dipoles at perovskite heterointerfaces.
abstract: The concept 'the interface is the device' is embodied in a wide variety of interfacial electronic phenomena and associated applications in oxide materials, ranging from catalysts and clean energy systems to emerging multifunctional devices. Many device properties are defined by the band alignment, which is often influenced by interface dipoles. On the other hand, the ability to purposefully create and control interface dipoles is a relatively unexplored degree of freedom for perovskite oxides, which should be particularly effective for such ionic materials. Here we demonstrate tuning the band alignment in perovskite metal-semiconductor heterojunctions over a broad range of 1.7 eV. This is achieved by the insertion of positive or negative charges at the interface, and the resultant dipole formed by the induced screening charge. This approach can be broadly used in applications where decoupling the band alignment from the constituent work functions and electron affinities can enhance device functionality.
authors: 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Department of Materials Engineering, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan.
authors: Takeaki
authors: T
authors: Yajima
authors: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors: Yasuyuki
authors: Y
authors: Hikita
authors: 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305, USA.
authors: Makoto
authors: M
authors: Minohara
authors: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
authors: Christopher
authors: C
authors: Bell
authors: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors: Julia A
authors: JA
authors: Mundy
authors: 1] School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA [2] Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors: Lena F
authors: LF
authors: Kourkoutis
authors: 1] School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA [2] Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors: David A
authors: DA
authors: Muller
authors: Photon Factory, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan.
authors: Hiroshi
authors: H
authors: Kumigashira
authors: Department of Applied Chemistry, The University of Tokyo, Bunkyo, Tokyo 113-8656, Japan.
authors: Masaharu
authors: M
authors: Oshima
authors: 1] Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA [2] Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305, USA.
authors: Harold Y
authors: HY
authors: Hwang