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This article reports on the RIXS (Resonant inelastic X-ray scattering), XES (X-ray emission spectroscopy), and XAS (X-ray absorption spectroscopy) of the LaSr 2 Mn 2 O 7 , La 0.95 Ba 0.05 MnO 3 , and La 1.2 (BaCa) 1.8 Mn 2 O 7 at 40 K, 100 K and 300 K. The RIXS spectra of these samples show the presence of Mn in different valence states (Mn2+, Mn3+, and Mn4+) which is associated with the Jahn-Teller distortion due to overlapping between O2− and the unpaired electrons of transition metal Mn. It has also been noticed that the distortion observed in different valence states of Mn with O2− is found to be suppressed with dropping and the temperature. So, based on aforementioned studies, the Manganites have been considered as a strongly correlated magnetic system which would be useful in magnetic device applications. • Studies on the RIXS, XES, XAS of single crystal LaSr2Mn2O7, La0.95Ba0.05MnO3, and La1.2(BaCa)1.8Mn2O7. • Different valence states of Mn have been probed under different temperatures. • Jahn-Teller distortion have been observed in Mn-O bonds due to overlapping of 3d and 2p states, respectively. • Studies of different electronic structure reflect manganites as strongly correlated magnetic system. • Suitable and potential candidates for magneto-caloric, magnetoresistance and magnetic device applications. [ABSTRACT FROM AUTHOR]

Eu-doped Sr 2 SnO 4 samples were synthesized using conventional ceramic route, followed by calcination at 1000 °C. Rietveld refinement analysis of XRD data indicates that the samples are single phase and crystallized into tetragonal crystal structure. Functional groups and metal-oxygen interaction has been studied using FTIR spectroscopy. The XPS analysis revealed the presence of oxygen vacancy, Sr in Sr2+ and Sn in Sn2+/Sn4+ in sample. The PL spectrum shows five peaks of Eu3+ due to transition 5D 0 →7F 0,1,2,3,4. The transition peaks 5D 0 →7F 0 and 5D 0 →7F 2 found most intense in PL spectra, and their ratio with 5D 0 →7F 1 were increased up to SSE6 and then decreased for SSE10, due to quenching phenomenon. An efficient energy transfer from oxygen vacancy to 5D 0 →7F 0 state leads to enormously increase in their intensity. By utilizing these absorption states and emission states as metastable state, the present sample can be used in UV-filter, UV-detector, and optical device applications. [ABSTRACT FROM AUTHOR]

Abstract: Anomalous Rabi oscillations in single and bilayer graphene, in the absence of time-reversal symmetry, are described. The main findings of this work are that intra-layer sublattice space asymmetry has a remarkable effect on anomalous Rabi frequency in single and bilayer graphene, namely it is offset by the asymmetry parameter. However, the conventional Rabi frequency is nearly independent of the asymmetry parameter. Inter-layer asymmetry in bilayer graphene has an even more significant effect on anomalous Rabi frequency. When inter-layer asymmetry is taken into account, the anomalous Rabi frequency versus the external field goes through a minimum. The induced current in the frequency domain in these systems shows a finite threshold behavior even for vanishingly small applied fields. These offset oscillations are attributable to the asymmetry parameter in these systems, and are observable only for weak applied fields. For stronger applied fields these phenomena tend towards those without asymmetry. [Copyright &y& Elsevier]

Abstract: We report a systematic study on growth of 2% and 4% Samarium (Sm) substituted lead zirconate titanate (PZT) thin films (with molar ratio of Zr:Ti::65/35) by sol gel technique on Pt/Si 〈100〉 and Pt/Si 〈111〉 substrates. XRD analysis show single phase for all films. Surface morphology was studied using atomic force microscope (AFM). A metal/ferroelectric/metal (MFM) structure was formed by depositing gold electrode on top of the film for electrical measurements (I–V (current vs voltage), C–V (capacitance vs voltage), P–E (polarization vs electric field)). The films show well-defined ferroelectric behaviour for both compositions (2% and 4% Sm-substituted PZT). I–V measurements show a compositional shift along −ve (negative) voltage axis. To obtain optical band gap, films were deposited on fused quartz and transmittance measurements were performed. Optical band gap was calculated from (αhυ)2 vs hυ graph (where α is the extinction coefficient, h the planck''s constant and υ the frequency of light). The results are discussed. [Copyright &y& Elsevier]