A5103237008- Surface and Thin Film Phenomena
- Graphene research and applications
- Quasicrystal Structures and Properties
- 2D Materials and Applications
- X-ray Diffraction in Crystallography
- Molecular Junctions and Nanostructures
- Microstructure and mechanical properties
- Electronic and Structural Properties of Oxides
- MXene and MAX Phase Materials
- Advanced Chemical Physics Studies
- Semiconductor materials and interfaces
- Inorganic Chemistry and Materials
- Organic and Molecular Conductors Research
- Nanocluster Synthesis and Applications
- Mineralogy and Gemology Studies
- Shape Memory Alloy Transformations
- nanoparticles nucleation surface interactions
- Iron-based superconductors research
- Rare-earth and actinide compounds
- Magnetic and transport properties of perovskites and related materials
- Topological Materials and Phenomena
- Anodic Oxide Films and Nanostructures
- Heusler alloys: electronic and magnetic properties
- Synthesis and characterization of novel inorganic/organometallic compounds
- Advanced Radiotherapy Techniques
Institut Jean Lamour
2024-2025
UGC DAE Consortium for Scientific Research
2018-2024
Centre National de la Recherche Scientifique
2024
University of Waterloo
2024
Dr. Bhim Rao Ambedkar University
2024
Université de Lorraine
2024
Devi Ahilya Vishwavidyalaya
2020
Ganesh Shankar Vidyarthi Memorial Medical College
2004
LaTe3 is a non-centrosymmetric material with time reversal symmetry, where the charge density wave hosted by Te bilayers. Here, we show that hosts Kramers nodal line-a twofold degenerate line connecting reversal-invariant momenta. We use angle-resolved photoemission spectroscopy, functional theory an experimentally reported modulated structure, effective band structures calculated unfolding, and symmetry arguments to reveal line. Furthermore, calculations confirm imposes gapless crossings...
Intermetallic compounds have shown promising catalytic properties, exhibiting better selectivity and thermal stability than their metallic counterparts. Understanding surface properties is crucial for optimizing performance. Here, we present an investigation of the atomic structure, chemical composition, oxidation behavior previously unexplored binary intermetallic catalyst, <a:math...
The electronic structure of Au-Sn intermetallic layers different compositions grown on Au(111) to the thickness several nanometers has been studied in this paper. layer, interface, and substrate related components Au $4f$ Sn $4d$ core-level spectra obtained using x-ray photoelectron spectroscopy (XPS) vary with deposition parameters reveal details formation. While AuSn is by at room temperature, rich compounds form as a result heat treatment through interdiffusion Sn. Deposition high...
The influence of disorder on the critical electron states in a quasiperiodic lattice is subject intense research. In this work, we report occurrence Anderson localization an icosahedral (i) polygrain quasicrystal Al-Pd-Re due to site using hard x-ray photoemission spectroscopy, resistivity, and density functional theory (DFT). Photoemission spectroscopy shows that enhanced at Fermi level $i$-Al-Pd-Re compared single-grain $i$-Al-Pd-Re. contrast, conductivity former order magnitude reduced...
Bimetallic Ni–Fe catalysts (Ni/Fe, 1 : 1, 3, and 3 1) are synthesized explored for their catalytic activity in semihydrogenation of internal alkynes using H<sub>2</sub> gas water–ethanol solution.
The bulk electronic structures of two high-order quaternary approximants F-type icosahedral (i)-Al-Pd-TM quasicrystal: Al-Pd-Cr-Fe and Al-Pd-Mo-Fe, having similar electron to atom (e/a) ratio as i-Al-Pd-Mn quasicrystal, have been investigated by hard x-ray photoelectron spectroscopy. We establish the presence a well-formed pseudogap at Fermi level in both approximants. turns out be deeper compared i−Al−Pd−Mn, this is supported specific heat data. Modifications line shape Al 2s core-level...
${\mathrm{CeMnNi}}_{4}$ exhibits an unusually large spin polarization, but its origin has baffled researchers for more than a decade. We use bulk sensitive hard x-ray photoelectron spectroscopy (HAXPES) and density functional theory based on the Green's function technique to demonstrate importance of electron-electron correlations both Ni $3d$ (${U}_{\text{Ni}}$) Mn (${U}_{\text{Mn}}$) electrons in explaining valence band this multiply correlated material. show that Mn-Ni antisite disorder...
The spontaneous ordering of a two-dimensional (2D) SrTiO3-derived film supported on Pt(111)/Al2O3(0001) is investigated by scanning tunneling microscopy. After annealing under ultrahigh vacuum, 2D reduced wetting layer formed where oxide quasicrystal approximants are observed. Upon increasing the number preparation cycles, Sr content in decreases. structure then evolves into Ti2O3 honeycomb (HC) lattice partially decorated adatoms. latter localized hollow sites network, with several complex...
Realization of an elemental solid-state quasicrystal has remained a distant dream so far in spite extensive work this direction for almost two decades. Here, we report the discovery quasiperiodic ordering thick layer Sn grown on icosahedral ($i$)-Al-Pd-Mn. The STM images and LEED patterns show specific structural signatures that portray quasiperiodicity but are distinct from substrate. Photoemission spectroscopy reveals existence pseudogap around Fermi energy up to maximal thickness....
A combined study employing density functional theory (DFT) using the experimentally determined modulated structures in martensite phase and bulk-sensitive hard x-ray photoelectron spectroscopy of stoichiometric single-crystalline ${\mathrm{Ni}}_{2}\mathrm{MnGa}$ is presented this paper. The experimental valence band (VB) features closely match theoretical VB calculated by DFT generalized gradient approximation for both austenite phases. We establish existence a charge wave (CDW) state from...
We report a comparative study of the bulk electronic structure two Al-based complex metallic alloys (CMAs), $\ensuremath{\beta}\ensuremath{-}{\mathrm{Al}}_{3}{\mathrm{Mg}}_{2}$ and ${\mathrm{Al}}_{13}{\mathrm{Fe}}_{4}$ using hard x-ray photoemission spectroscopy (HAXPES) interpreted on basis density functional theory (DFT) calculations. An experimental confirmation role Hume-Rothery mechanism for stability phase is established by identification shallow pseudogap near ${E}_{F}$ from HAXPES...
By employing x-ray photoelectron spectroscopy, we present a detailed study of the core level spectra LaTe3 in its charge density wave phase at room temperature. The analysis Te 3d spectrum by curve fitting using least square error minimization reveals that atoms exist two different states: Te-Te layer has valency −0.5, whereas atom La-Te −2. La shows three peaks for each spin orbit component, where main peak and satellite appear due to final states related transfer from ligand states.
The flexibility of amorphous anodized alumina (AAO) in developing radiation dosimeter for hadron therapy is reported by controlled carbon ion implantation, followed thermoluminescence (TL) measurements. efficacy AAO controlling TL sensitivity found to be governed an increase F+ defect centers as a function concentration, revealed from the close resemblance trend photoluminescence intensity. Moreover, its nanoporous structure demonstrated advantageous engineering due surface-to-volume ratio....
Abstract Abstarct. Two dimensional (2D) derivatives of tin (Sn) have obtained special deliberations recently due to practical realization planar, as well as, buckled hexagonal lattice Sn called stanene. However, it has been observed that proper choice substrate is very important for growth stanene like films owing large core size prefers sp 3 hybridization over 2 . Transition metal dichalcogenides (TMDs) MoS or WS with honey comb structure seem be promising candidates 2D Sn. In the present...
In the present paper, we report a comprehensive study of effect annealing temperature in ultra-high vacuum on icosahedral (i)-Al-Pd-Mn surface using low energy electron diffraction (LEED) and scanning tunneling microscopy (STM). The preparation i-Al-Pd-Mn is important for growing elemental quasiperiodic layers. LEED pattern shows spots with high background after at 823 K whereas sharp less are observed when annealed 923 K. On other hand, STM presence clusters diameters 5 to 40 nm heights 1...
Although quasicrystals have been discovered more than 30 years back and many ternary binary alloys shown to exhibit quasicrystallinity, until date elemental remained elusive. One approach achieve this goal has investigate whether quaicrystallinity can be induced in a crystalline material by growing it on quasicrystalline substrate. Here, we establish 10-fold quasiperiodicity of one monolayer Sn grown d-Al-Ni-Co at room temperature using low energy electron diffraction Auger spectroscopy.
We study the effect of different surface preparation conditions on 10-fold decagonal (d)-Al-Ni-Coquasicrystal using low energy electron diffraction (LEED), scanning tunneling microscopy (STM) and Auger spectroscopy (AES). It is observed that after rare gas ion sputtering process, annealing time period (tA) at a temperature 1043K plays an important role in obtaining clean, stoichiometric quasicrystalline with flat terraces 1043 K.
On the basis of x-ray photoelectron spectroscopy, we show that when Sn is deposited on Au(111) single crystal surface at a substrate temperature TS=373 K, alloying occurs with formation AuSn phase. The evolution structure and morphology has been studied by low energy electron diffraction scanning tunneling microscopy, respectively as function coverage temperatures.
We demonstrate unexpected occurrence of linear bands resembling Dirac cone at the zone-center Au$_2$Sn surface alloy with $\left( \begin{smallmatrix} 2&1\\ 1&3 \end{smallmatrix} \right)$ structure formed by deposition about 0.9 ML Sn on Au(111) elevated temperature. The exhibits an oblique symmetry unequal lattice constants making it first two dimensional to exhibit a non-honeycomb lattice.
We report here on room temperature (RT) adsorption of Sn atoms mechanically cleaved WS2 hexagonal crystal surface under ultra-high vacuum (UHV) conditions. Our in-situ low energy electron diffraction (LEED) and scanning tunneling microscopy (STM) studies clearly indicate atomic configurations bare adsorbed surfaces. Bare displays an periodicity with lattice constant, a, as 0.34 nm. RT indicates a nearly commensurate W or S sites lateral distance between two ∼0.325 nm bond length W/S ∼40 pm....