15 research outputs found
Observation of multiple van Hove singularities and correlated electronic states in a new topological ferromagnetic kagome metal NdTi3Bi4
Kagome materials have attracted enormous research interest recently owing to
its diverse topological phases and manifestation of electronic correlation due
to its inherent geometric frustration. Here, we report the electronic structure
of a new distorted kagome metal NdTi3Bi4 using a combination of angle resolved
photoemission spectroscopy (ARPES) measurements and density functional theory
(DFT) calculations. We discover the presence of two at bands which are found to
originate from the kagome structure formed by Ti atoms with major contribution
from Ti dxy and Ti dx2-y2 orbitals. We also observed multiple van Hove
singularities (VHSs) in its electronic structure, with one VHS lying near the
Fermi level EF. In addition, the presence of a surface Dirac cone at the G
point and a linear Dirac-like state at the K point with its Dirac node lying
very close to the EF indicates its topological nature. Our findings reveal
NdTi3Bi4 as a potential material to understand the interplay of topology,
magnetism, and electron correlation.Comment: 7 pages, 4 figure
Discovery of a magnetic Dirac system with large intrinsic non-linear Hall effect
Magnetic materials exhibiting topological Dirac fermions are attracting
significant attention for their promising technological potential in
spintronics. In these systems, the combined effect of the spin-orbit coupling
and magnetic order enables the realization of novel topological phases with
exotic transport properties, including the anomalous Hall effect and
magneto-chiral phenomena. Herein, we report experimental signature of
topological Dirac antiferromagnetism in TaCoTe2 via angle-resolved
photoelectron spectroscopy (ARPES) and first-principles density functional
theory (DFT) calculations. In particular, we find the existence of spin-orbit
coupling-induced gaps at the Fermi level, consistent with the manifestation of
a large intrinsic non-linear Hall conductivity. Remarkably, we find that the
latter is extremely sensitive to the orientation of the N\'eel vector,
suggesting TaCoTe2 a suitable candidate for the realization of non-volatile
spintronic devices with an unprecedented level of intrinsic tunability
Observation of multiple flat bands and topological Dirac states in a new titanium based slightly distorted kagome metal YbTi3Bi4
Kagome lattices have emerged as an ideal platform for exploring various
exotic quantum phenomena such as correlated topological phases, frustrated
lattice geometry, unconventional charge density wave orders, Chern quantum
phases, superconductivity, etc. In particular, the vanadium based nonmagnetic
kagome metals AV3Sb5 (A= K, Rb, and Cs) have seen a flurry of research interest
due to the discovery of multiple competing orders. Here, we report the
discovery of a new Ti based kagome metal YbTi3Bi4 and employ angle-resolved
photoemission spectroscopy (ARPES), magnetotransport in combination with
density functional theory calculations to investigate its electronic structure.
We reveal spectroscopic evidence of multiple flat bands arising from the kagome
lattice of Ti with predominant Ti 3d character. Through our calculations of the
Z2 indices, we have identified that the system exhibits topological
nontriviality with surface Dirac cones at the Gamma point and a quasi
two-dimensional Dirac state at the K point which is further confirmed by our
ARPES measured band dispersion. These results establish YbTi3Bi4 as a novel
platform for exploring the intersection of nontrivial topology, and electron
correlation effects in this newly discovered Ti based kagome lattice.Comment: 8 pages, 5 figure
Utilizing Reduced Graphene Oxide-Iron Nanoparticles Composite to Enhance and Accelerate the Removal of Methyl Blue Organic Dye in Wastewater
In this work, a nano-composite is used to remove dye from wastewater of different industries. For this purpose, thesynthesis of a magnetic 1:1 composite made of iron nanoparticles (NPs) using reduced graphene oxide is a novel techniqueand tested for Methyl Blue (MB) dye adsorption from aqueous solution. In this study Fe nanoparticles in reduced Graphenecomposite (FGOC) has been prepared using Graphene Oxide (GO). X-ray diffraction, FTIR spectroscopy and Ramanspectroscopy, are used to identify the structures. Many methods have been developed for MB removal in wastewater. One ofthe most popular methods is adsorption because it is simple and high-efficiency, and the adsorbent is crucial. It reached amaximum MB adsorption at pH 7. The kinetic study indicated that the adsorption of MB process was fitted well to thequasi-first-order and quasi-second-order kinetic models. The isotherm study revealed that the MB adsorption process obeyedthe Langmuir and Freundlich adsorption Isotherms models. The GO adding content and absorption conditions on the methylblue removal efficiencies were investigated. This adsorbent is easily recovered by an external magnetic field from thetreated wastewater and has high reusability
An imperfect production inventory model with advance payment and credit period in a two-echelon supply chain management
This paper presents an integrated imperfect production inventory model under two layer supply chain management. To ensure the orders, manufacturer convinces the retailer to pay a percentage of the purchasing cost prior to replenish the products and offers the facilities such as (i) delay in payment on the remaining part of the purchasing cost and (ii) free transportation on the basis of advance payment amount. Time dependent development cost is incurred to maintain the reliability of the production system and as a result it reduces the imperfectness of the product during production. Under such circumstances, an integrated profit function has been developed to find the optimum number of production cycle, optimum number of replenishment cycle and hence reliability parameter of the manufacturing system, replenishment quantity for the retailer which maximize the integrated profit. Branch and Bound technique is used to obtain the integer solutions. Furthermore, we derived some useful lemmas and algorithms to obtain the optimum solution. Finally, the model has been illustrated with some numerical examples exploring the sensitivity analysis with respect to some parameters and obtains some managerial insights