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We have studied the spin-dependent electron momentum density distribution in CoGaFeO ( x = 0.2, 0.3) at a low temperature (8 K) using magnetic Compton scattering technique. Further, the effect of Ga doping on the electronic structure is studied using X-ray photoemission spectroscopy (XPS). It is revealed that doping of Ga substitutes the Fe ions predominantly at tetrahedral (P) site, which promotes a gradual immigration of small amount of Co ions from tetrahedral to octahedral (Q) site. Total spin moment increases remarkably on increasing the doping concentration of nonmagnetic Ga ( x = 0 → 0.3) in the base cobalt ferrite. It is seen that major contribution to total spin moment mainly arises from Co ions while itinerant electrons show negative polarization. On Ga doping, spin moment at Fe site increases dramatically with a minor increment at Co site. The increased spin moment is attributed to the increased Q/P occupancy ratio of Fe as well as Co ions as determined using XPS measurements. In contrast, orbital moment does not show such deviations, suggesting that a small amount of Ga doping can enhance the magnetization significantly, without inducing any significant distortion to modify the spin-orbit coupling. [ABSTRACT FROM AUTHOR]

We have studied the electronic transport behaviour and band offset properties of the epitaxial TiO2-x (x = 0.05)/La0.7Sr0.3MnO3 hetero-structure. The bilayer shows non-linear I-V characteristics at different temperatures as well as negative magneto-resistance with the application of magnetic field. Valence band offset (VBO) was measured using photoelectron spectroscopy and consequently the conduction band offset (CBO) was determined. It is found that type-I alignment takes place at the interface. The value for CBO (1.1 eV) is much lower than VBO (2.3 eV), suggesting that transport is mainly dominated by electrons. Observed negative magneto-resistance in such bilayer is explained with the help of band structure of La0.7Sr0.3MnO3. [ABSTRACT FROM AUTHOR]

We present the first-ever experimental Compton profile of Laves phase ZrFe 2 using indigenous 20 Ci 137 Cs Compton spectrometer. To annotate the experimental electron momentum density, we have calculated the theoretical Compton profiles using density functional theory (DFT) and hybridization of Hartree–Fock and DFT within linear combination of atomic orbitals (LCAO) method. The spin-polarized energy bands and density of states are computed using LCAO and full potential-linearized augmented plane wave methods. The revised Perdew-Burke-Ernzerhof functional (for solids) based theoretical profile gives a marginally better agreement with the experimental profile as compared to other approximations considered in the present work. The Fermi surface topology of ZrFe 2 is explained in terms of majority- and minority-spin energy bands. [ABSTRACT FROM AUTHOR]

Highlights: [•] Sol–gel grown polycrystalline single phasic Zn1 − x Co x O system is synthesized. [•] X-ray Photoemission spectroscopy reveals that, Co-substitution results in the EF shift and chemical shift in ZnO. [•] Co-substitution induced electronic structure and valence band modifications in Zn1 − x Co x O (x =0, 0.5 and 0.15) samples. [•] Co 3d states around 3.4eV show resonance at ∼62eV and are hybridized with O 2p bonding states. [ABSTRACT FROM AUTHOR]