TY - JOUR
KW - Atoms
KW - Heterojunctions
KW - Electronic structure
KW - Probability density function
KW - Coincidence site lattices
KW - Conduction-band minimum
KW - Density function theory calculations
KW - Experimental methods
KW - Heterojunction interfaces
KW - Interfacial electronic structure
KW - Lattice-mismatched
KW - Valence-band maximums
AU - S Wang
AU - B Kavaipatti
AU - S.-J Kim
AU - X Pan
AU - Ramamoorthy Ramesh
AU - J .W III
AU - L.-W Wang
AB - Heterojunction interfaces between metal oxides are often highly lattice mismatched. The atomic and electronic structures of such interfaces, however, are not well understood. We have synthesized Cu2O/TiO2 heterojunction thin films with 13% lattice mismatch and studied the interface via experimental methods and large-scale density function theory calculations of supercells containing ∼1300 atoms. We find that an interface of epitaxial quality is formed via a coincidence site lattice of 8 Cu2O unit cells matching 9 TiO2 unit cells. Calculations reveal the existence of a dislocation core of the O sublattices at the interface and a random arrangement of one layer of interfacial Cu atoms. The interfacial electronic structure is found to be mostly determined by the interfacial Cu distribution, rather than by the O dislocation core. The conduction band minimum and valence band maximum states are spatially separated, and there is no strongly localized state near the core. © 2014 AIP Publishing LLC.
BT - Applied Physics Letters
DO - 10.1063/1.4880942
LA - eng
M1 - 21
N1 - cited By 4
N2 - Heterojunction interfaces between metal oxides are often highly lattice mismatched. The atomic and electronic structures of such interfaces, however, are not well understood. We have synthesized Cu2O/TiO2 heterojunction thin films with 13% lattice mismatch and studied the interface via experimental methods and large-scale density function theory calculations of supercells containing ∼1300 atoms. We find that an interface of epitaxial quality is formed via a coincidence site lattice of 8 Cu2O unit cells matching 9 TiO2 unit cells. Calculations reveal the existence of a dislocation core of the O sublattices at the interface and a random arrangement of one layer of interfacial Cu atoms. The interfacial electronic structure is found to be mostly determined by the interfacial Cu distribution, rather than by the O dislocation core. The conduction band minimum and valence band maximum states are spatially separated, and there is no strongly localized state near the core. © 2014 AIP Publishing LLC.
PB - American Institute of Physics Inc.
PY - 2014
T2 - Applied Physics Letters
TI - Atomic and electronic structures of lattice mismatched Cu 2O/TiO2 interfaces
VL - 104
SN - 00036951
ER -