Electronic band structure and carrier effective mass in calcium aluminates

Abstract

First-principles electronic band structure investigations of five compounds of the CaO-Al2O3 family, 3CaO.Al2O3, 12CaO.7Al2O3, CaO.Al2O3, CaO.2Al2O3 and CaO.6Al2O3, as well as CaO and alpha-, theta- and kappa-Al2O3 are performed. We find that the conduction band in the complex oxides is formed from the oxygen antibonding p-states and, although the band gap in Al2O3 is almost twice larger than in CaO, the s-states of both cations. Such a hybrid nature of the conduction band leads to isotropic electron effective masses which are nearly the same for all compounds investigated. This insensitivity of the effective mass to variations in the composition and structure suggests that upon a proper degenerate doping, both amorphous and crystalline phases of the materials will possess mobile extra electrons.

References in corpus (8)

• Electronic structure of the MO oxides (M=Mg, Ca, Ti, V) in the GW approximation
• Magnetically Mediated Transparent Conductors: In${}_2$O${}_3$ doped with Mo
• Hopping versus bulk conductivity in transparent oxides: 12CaO.7Al2O3
• Averaging of the electron effective mass in multicomponent transparent conducting oxides
• Combining high conductivity with complete optical transparency: A band-structure approach
• Electronic structure and light-induced conductivity in a transparent refractory oxide
• Tunable Conductivity and Conduction Mechanism in a UV light activated electronic conductor
• Unconventional approaches to combine optical transparency with electrical conductivity

Cited by in corpus (3)

• Tuning the properties of complex transparent conducting oxides: role of crystal symmetry, chemical composition and carrier generation
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• Effect of interface geometry on electron tunnelling in Al/Al${}_2$O${}_3$/Al junctions