Experimental and theoretical study of the electronic structure of single-crystal BaBiO₃
department or school: Science, Faculty of
department or school: Physics and Astronomy, Department of
data provider: DSpace
degree campus: UBCV
creator: Balandeh, Shadi
issued: 2018-08-27T17:21:05Z
issued: 2018
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Hole doped bismuth perovskite is one of the rare examples of a three-dimensional high transition temperature superconducting oxide (Tc = 34 K) without a transition metal cation. The undoped compound, BaBiO₃, also shows closely interlinked electronic and structural phase transitions and a controversial insulating mechanism. Understanding the electronic structure of the parent compound, BaBiO₃, can give valuable insight into both its superconducting mechanism, in particular, and into the physics of the perovskites family, in general. In this work, we first grow high-quality single crystals of BaBiO₃ by congruent melting technique and characterize the crystals with x-ray di ffraction, x-ray photoemission, and transport properties measurements. We then investigate the electronic structure of the material from both theoretical and experimental perspectives. Experimentally, we study the crystals through x-ray absorption, x-ray emission, and photoelectron spectroscopies. X-ray spectroscopy verfi es the results of density functional theory (DFT) regarding the overall band structure featuring strong O 2p character of the empty anti-bonding combination of the hybridized Bi 6s and O 2p states. We also develop a routine to successfully clean the sample's surface in order to achieve the intrinsic O 1s x-ray photoemission spectrum. Finally, we employ the "exact diagonalization single cluster con figuration interaction" method to investigate the ground state electronic structure of the material and to understand the measured O 1s x-ray photoemission result. From the analysis of the core level line shapes, we conclude that the dominant O 2p-Bi 6s hybridization energy scale determines the low energy scale electronic structure. We also find that for a wide range of electronic parameters, the holes reside primarily on the ligand oxygen anions rather than the bismuth cation consistent with the band structure calculation but contrary to what is traditionally assumed for this material. T…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/66955
note: Experimental and Theoretical Studyof The Electronic Structure ofSingle-crystal BaBiO3byShadi BalandehB.Sc., Sharif University of Technology, 2011M.Sc., The University of British Columbia, 2013A THESIS SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFDOCTOR OF PHILOSOPHYinThe Faculty of Graduate and Postdoctoral Studies(Physics)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)August 2018c© Shadi Balandeh 2018The following individuals certify that they have read, and recommendto the Faculty of Graduate and Postdoctoral Studies for acceptance, thedissertation entitled:Experimental and Theoretical Study of The Electronic Structure ofSingle-crystal BaBiO3submitted by Shadi Balandeh in partial fulfillment of the requirementsfor the degree of Doctor of Philosophy in Physics.Examining Committee:Supervisor: Prof. George A. SawatzkySupervisory Committee Member: Prof. Doug BonnSupervisory Committee Member: Prof. Mona BerciuSupervisory Committee Member: Prof. Mark Van RaamsdonkUniversity Examiner: Prof. Srikantha PhaniUniversity Examiner: Prof. Sarah BurkeiiAbstractHole doped bismuth perovskite is one of the rare examples of a three-dimensional high transition temperature superconducting oxide (Tc = 34K) without a transition metal cation. The undoped compound, BaBiO3,also shows closely interlinked electronic and structural phase transitions anda controversial insulating mechanism. Understanding the electronic struc-ture of the parent compound, BaBiO3, can give valuable insight into bothits superconducting mechanism, in particular, and into the physics of theperovskites family, in general.In this work, we first grow high-quality single crystals of BaBiO3 by con-gruent melting technique and characterize the crystals with x-ray diffraction,x-ray photoemission, and transport properties measurements.We then investigate the electronic structure of the material from boththeoretical and experimental perspectives. Experimentally, we study thecrystals through x-ray absorp…
has type: Thesis/Dissertation
date issued: 2018-09
is shown at: 10.14288/1.0371243
language: eng
degree discipline: Physics
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/66955