Surface reconstruction of hexagonal Y-dopedHoMnO3andLuMnO3studied using low-energy electron diffraction

Abstract

We have investigated the (0001) surfaces of several hexagonal manganite perovskites by low-energy electron diffraction (LEED) in order to determine if the surface periodicity is different from that of the bulk materials. These LEED studies were conducted using nearnormal incidence geometry with a low energy electron microscope (LEEM)/LEED apparatus from room temperature to 1200°C and with an electron energy in the range of 15 -50 eV. Diffraction patterns showed features of bulk-terminated periodicity as well as a 2×2 surface reconstruction. Possible origins for this surface reconstruction structure are discussed and comparisons are made with surface studies of other complex oxides.2

Atomic Mechanism of Hybridization-Dependent Surface Reconstruction with Tailored Functionality in Hexagonal Multiferroics

“…Details of the polarization and charge distribution in the surface layers of multiferroics and their relationship to the physical properties of materials have been studied for decades and are largely unresolved . Several possible mechanisms have been proposed to explain the different nature of surface layers with bulk, including nonuniform vacancy distributions, compensation of polarization-induced charges by band bending (intrinsic field effect) or adsorption (extrinsic field effect), and the existence of Schottky depletion regions. , These considerations have motivated a number of surface investigations using X-ray characterization, scanning tunneling microscopy, low-energy electron diffraction, and so forth. However, limitations such as restricted spatial resolution, requiring electrical conductivity, or complexity of tip–surface interactions are naturally embedded in these methods.…”