http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/866 2026-04-29T11:23:39Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/873 Title: Study of the Fe2CoAl heusler alloy films growth on the R-plane sapphire substrate by scanning probe microscopy Authors: Rai, Dibya Prakash Abstract: The grown films of FCA Heusler alloy on the R-plane sapphire with and without the W (001) seed layer were studied using scanning atomic and magnetic force microscopies, supplemented with the results of micromagnetic calculations and measurements of film magnetoresistance. Nonmonotonic dependences of the films’ morphological and magnetic properties on their growth temperature caused, as assumed, by the formation of some disordered phase at temperatures of 50<Tg < 170 C with biaxial magnetic anisotropy were found. A more ordered phase grew in the temperature range 170<Tg < 400 C, in which there was the uniaxial magnetic anisotropy. 2019-07-09T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/871 Title: Electronic and optical properties of cubic SrHfO3 at different pressures: A first principles study Authors: Rai, Dibya Prakash Abstract: The electronic and optical properties of cubic SrHfO3 under the variation of pressures were investigated by first-principles calculation within the framework of generalized gradient approximation (GGA). The calculated equilibrium lattice constant of cubic SrHfO3 is in good agreement with available experimental and theoretical results. The result shows that SrHfO3 is an insulator with an indirect band gap up to 20.00 GPa, along . While the application of pressure above 20.00 GPa the band gap changes to direct band gap, along . The band gap increases from 3.80 eV to 4.11 eV with the increase in pressure from 0.00 GPa to 35.00 GPa. In order to understand the optical properties of SrHfO3 perovskite, the dielectric function, optical conductivity and electron energy loss are calculated for photon energy up to 14.00 eV. We have also observed the decrease in static dielectric constant with the increase in energy band gap under pressure 2016-11-23T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/870 Title: Ferromagnetism in d0 Binary Compounds MC (M = Be, Mg, Ca, Sr, Ba and Ra): A Modified Becke Johnson Potential Study Authors: Rai, Dibya Prakash Abstract: We have performed the FP-LAPW calculation based on the density functional theory (DFT) to study the electronic and magnetic properties of binary compounds MC (M = Be, Mg, Ca, Sr, Ba and Ra). The density of states (DOS) and band structures were studied to understand the electronic properties. We have employed an orbital independent semilocal exchange potential called modified Becke Johnson (mBJ) which includes a large proportion of electrons residing in the intestinal regions. Thus the information obtained from mBJ is more accurate as compared to conventional DFTs (GGA/LDA) as their potential is electron orbital dependent. Among the systems under our investigation CaC, SrC, BaC and RaC has given the 100% spin polarization at Fermi energy (EF) within GGA whereas mBJ open a gap for all the systems. The total magnetic moment was found to be 2.00 B which is an integer value as expected for the HMF systems. The large half metallic gaps and location of EF was found to be robust with respect to lattice constants in RaC and BeC 2016-01-01T00:00:00Z