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Lead-free double perovskite materials (viz., Cs2AgInCl6) are being explored as stable and nontoxic alternatives of lead halide perovskites. In order to expand the optical response of Cs2AgInCl6 in the visible region, we report here on the stability, electronic structure, and optical properties of Cs2AgInCl6 by sublattice mixing of various elements. We have employed a hierarchical first-principles-based approach starting from density functional theory (DFT) with appropriate exchange-correlation functionals to beyond DFT methods under the framework of many body perturbation theory (viz., G0W0@HSE06). We have started with 32 primary set of combinations of metals M(I), M(II), M(III), and halogen X at Ag/In and Cl sites, respectively, where the concentration of each set is varied to build a database of nearly 140 combinations. The most suitable mixed sublattices are identified to engineer the bandgap of Cs2AgInCl6 to have its application in optoelectronic devices under visible light. [ABSTRACT FROM AUTHOR]

Simultaneously achieving higher carriers concentration and mobility is a technical challenge against up-scaling the transparent-conductive performances of transparent-conductive oxides. Utilizing one order higher dense (~1 × 1011 cm-3) plasmas (in comparison to the conventional direct current plasmas), highly c-axis oriented Al-doped ZnO films have been prepared with precise control over relative composition and chemical states of constituting elements. Tailoring of intrinsic (O vacancies) and extrinsic (ionic Al and zero-valent Al) dopants provide simultaneous enhancement in mobility and concentration of charge carriers. Room-temperature resistivity as low as 4.89 × 10-4 Ω cm along the carrier concentration 5.6 × 1020 cm-3 is obtained in 200 nm thick transparent films. Here, the control of atomic Al reduces the charge trapping at grain boundaries and subdues the effects of grain boundary scattering. A mechanism based on the correlation between electron-hole interaction and carrier mobility is proposed for degenerately doped wide band-gap semiconductors. [ABSTRACT FROM AUTHOR]

Ferromagnetic and large magnetoresistance (MR) nanocomposites of La0.67Sr0.33MnO3-BaTiO3 (LSMO-BTO) are synthesized via sol-gel route. The X-ray diffraction confirms the existence of two chemically separated phases in the composites. The maximum MR (35%) was achieved in LSMO-5% BTO (LB5). The coupling between the coexisting phases is observed from the dielectric anomaly at the ferromagnetic transition (Tc=353 K) for LB5 composition. We observed maximum magnetodielectric effect at Tc of 1.18% in magnitude for LB5 and the effect of magnetic field on other composites was significant. These results are related to the large spin polarization within grains as well as at the grain boundaries and the evidence of variation in dielectric parameters with magnetic field reveal the magnetoelectric coupling in LSMO-BTO nanocomposites. [ABSTRACT FROM AUTHOR]

We propose a simple and straightforward method to generate spatially variant lattice structures by optical interference lithography method. Using this method, it is possible to independently vary the orientation and period of the two-dimensional lattice. The method consists of two steps which are: numerical synthesis of corresponding phase mask by employing a two-dimensional integrated gradient calculations and experimental implementation of synthesized phase mask by making use of a phase only spatial light modulator in an optical 4f Fourier filtering setup. As a working example, we provide the experimental fabrication of a spatially variant square lattice structure which has the possibility to guide a Gaussian beam through a 90° bend by photonic crystal self-collimation phenomena. The method is digitally reconfigurable, is completely scalable, and could be extended to other kind of lattices as well. [ABSTRACT FROM AUTHOR]

Electronic structure of pulsed laser deposited hexagonal-YMnO3 film on Al2O3 (0001) substrate has been investigated by photoemission spectroscopy using variable energy photon sources. Resonance photoemission results reveal the charge transfer nature of h-YMnO3 and variation in strength of hybridization between oxygen 2p and Mn 3d across the valence band region. The valence states sensitive to lattice distortion (inversion asymmetry) demonstrate the evolution of spin orbit interaction (SO). This SO along with its anisotropic behavior is well identified by the constant initial state plots. [ABSTRACT FROM AUTHOR]

Publisher's Note: "Sublattice mixing in Cs2AgInCl6 for enhanced optical properties from first-principles" [Appl. Phys Lett. HT ht (3) All online versions of the article were corrected on 19 January 2021. This article was originally published online on 15 January 2021 with an error in Eq. (3). [Extracted from the article]

A letter to the editor is presented in response to the article "Zero-field cooled exchange bias in hexagonal YMnO3 nanoparticles" that was published in the 2013 issue.