http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/865 Sun, 03 May 2026 03:52:53 GMT 2026-05-03T03:52:53Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/1041 Title: Study of energy bands and magnetic properties of Co2CrSi Heusler alloy Authors: Rai, Dibya Prakash Abstract: The electronic and magnetic properties of Co2CrSi is calculated by using full-potential linearized augmented plane wave (FP–LAPW) method based on density functional theory (DFT). Density of states (DOS), magnetic moment and band structures of the system are presented. For the exchange and correlation energy, local spin density approximation (LSDA+U) with the inclusion of Hubbard potential U is used. Our calculation shows indirect bandgap of 0·91 eV in the minority channel of DOS. This is supported by band structures and hence favoured the half metallic ferromagnetic (HMF) nature of the system. The effective magnetic moment of 4·006 μB also supported our conclusion with a near integral value. The DOS of Co and Cr were found to hybridize and was also responsible for the ferromagnetic nature of the system. Sat, 01 Oct 2011 00:00:00 GMT http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/1041 2011-10-01T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/872 Title: Perpendicular magnetocrystalline anisotropy energy (MAE) of 111-surface slab of Fe2CoAl Authors: Rai, Dibya Prakash Abstract: Wehave analyzed the surface stability of different orientations(111, 001, 011) of Fe2CoAl (FCA) slabs. Among all the slabs, the orientation with 111-surface is found to be most stable with minimum energy. The surface electronic and magnetic properties along with the atomic orbital resolved magnetocrystalline anisotropy energy (MAE) has been performed by using first principles density functional theory (DFT).We have reported the surface metallicity with dispersed electronic bands around the fermi energy (EF) in all the three terminals Fe/Co/Al. This may be the result of translational broken symmetry in which metallic bonds are broken with the release of free conducting electrons on the surface.Wehave observed the presence of both the in-planeMAEand the out-planeMAE characterized by the distribution of totalMAEover an atomic sites for each Al-, Co- and Fe-terminal. The totalMAEfavors in-plane magnetization in case of antiferromagnetic configured Al-terminal (MAE=0.034 meV) and Fe-terminal (0.68 meV) whereas out-plane totalMAEis observed in ferromagnetic configured Co-terminal. Fri, 05 Jun 2020 00:00:00 GMT http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/872 2020-06-05T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/869 Title: Electronic properties and low lattice thermal conductivity (kl) of mono-layer (ML) MoS2: FPLAPW incorporated with spin–orbit coupling (SOC) Authors: Rai, Dibya Prakash Abstract: This paper focuses on the electronic and thermoelectric properties of monolayer MoS2. Here, we have examined the structure of MoS2, in which the hole in the center of the hexagonal cage is considered as a void atom, termed 1H-MoS2. Density functional theory (DFT) employing the generalized gradient approximation (GGA) and spin–orbit coupling (SOC) has been used for all calculations. Incorporation of SOC resulted in a significant change in the profile of the band energy, specifically the splitting of the valence band maximum (VBM) into two sub-bands. The “split-off” energy is found to be 20.6 meV. The reduction of the band gap with SOC is a prominent feature at the K–K location in the Brillouin zone. The band gap calculated with the GGA is 1.75 eV. However, on implementation of SOC, the GGA band gap was reduced to 1.68 eV. The frequency-dependent phonon dispersion curve was obtained to analyse the thermodynamical stability. 1H-MoS2 is found to be thermodynamically stable with no imaginary frequency. We report a low value of lattice thermal conductivity (kl) and low electron effective masses low electron effective masses, which are desirable for potential applications in thermoelectric devices. Mon, 20 Apr 2020 00:00:00 GMT http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/869 2020-04-20T00:00:00Z http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/868 Title: Band-gap engineering of La1􀀀𝑥Nd𝑥AlO3 (𝑥 = 0,0.25,0.50,0.75, 1) perovskite using density functional theory: A modified Becke Johnson potential study Authors: Rai, Dibya Prakash Abstract: The structural, electronic, and magnetic properties of the Nd-doped Rare earth aluminate, La1􀀀xNdxAlO3 (x = 0% to 100%) alloys are studied using the full potential linearized augmented plane wave (FP-LAPW) method within the density functional theory. The effects of the Nd substitution in LaAlO3 are studied using the supercell calculations. The computed electronic structure with the modified Becke–Johnson (mBJ) potential based approximation indicates that the La1􀀀xNdxAlO3 alloys may possess half-metallic (HM) behaviors when doped with Nd of a finite density of states at the Fermi level (EF). The direct and indirect band gaps are studied each as a function of x which is the concentration of Nddoped LaAlO3. The calculated magnetic moments in the La1􀀀xNdxAlO3 alloys are found to arise mainly from the Nd-4f state. A probable half-metallic nature is suggested for each of these systems with supportive integral magnetic moments and highly spin-polarized electronic structures in these doped systems at EF. The observed decrease of the band gap with the increase in the concentration of Nd doping in LaAlO3 is a suitable technique for harnessing useful spintronic and magnetic devices. Wed, 20 Apr 2016 00:00:00 GMT http://pucir.inflibnet.ac.in:8080/jspui/handle/123456789/868 2016-04-20T00:00:00Z