927 research outputs found
Quantum Critical Phase and Lifshitz Transition in an Extended Periodic Anderson Model
We study the quantum phase transition in -electron systems as a quantum
Lifshitz transition driven by selective Mott localization in a realistic
extended Anderson lattice model. Using DMFT, we find that a quantum critical
{\it phase} with anomalous scaling separates a heavy Landau-Fermi
liquid from ordered phase(s). Fermi surface reconstruction occurs via the
interplay between, and penetration of the Green function zeros to the poles,
leading to violation of Luttinger's theorem in the selective-Mott phase . We
show how this naturally leads to scale-invariant responses in transport. Our
work is represents a specific (DMFT) realization of the hidden-FL and FL
theories, and holds promise for study of "strange" metal phases in quantum
matter.Comment: 8 pages,5 figure
Theoretical study on spintronic and optical property prediction of doped magnetic Borophene
Two dimensional materials are attracting new research for optoelectronics and
spintronics due to their unique physical properties. A wide range of emerging
spintronic devices are achieved from parent and doped two dimensional
materials. First-principles electronic structure calculations of a
two-dimensional monolayer of borophene in its P6/mmm form is explored in this
study. The electronic, magnetic, and optical properties of doped borophene are
analyzed for doping with lithium, sodium, and magnesium. Density functional
theory calculations advocate their good dynamical and thermal stability.
Spin-polarized electronic properties of these materials are observed to be
useful for predicting new spintronic materials. Additionally optical analysis
exhibits the absorption peaks in monolayers along the in-plane direction. These
properties of doped magnetic borophene suggest the material to be a suitable
candidate for designing optoelectronic devices. The most competent spintronic
material among three different doped borophenes is lithium doping that can
imply a promising avenue for the fast-growing electronics industry
Intercalation in 2H-TaSe 2 for modulation of electronic properties and electrochemical energy storage
Two-dimensional transition metal dichalcogenides (TMDs) exhibit an extensive
variety of novel electronic properties, such as charge density wave quantum
spin Hall phenomena, superconductivity, and Dirac and Weyl semi-metallic
properties. The diverse properties of TMDs suggest that structural
transformation can be employed to switch between different electronic
properties. Intercalation and zero valence doping of molecules and atoms into
the van der Waals gap of TMDs have emerged as effective approaches to modify
the charge order states of the material. This eventually leads to phase
transition or the formation of different phases, thus expanding the electronic,
thermoelectric and optical applications of these materials. In this study,
electronic and electrochemical energy storage properties of such an
intercalated TMD, namely, 2H-TaSe 2 via intercalation of lithium (Li), sodium
(Na) and potassium (K) have been investigated. The intercalation of these ions
into the dichalcogenide resulted in a modified band structure and novel
structural effects, leading to the emergence of a 1 eV band gap. Possibility of
electrochemical energy storage application is also explored in this study.
Furthermore, the importance of multi orbital electron-electron correlations in
intercalated TaSe 2 is also investigated via dynamical-mean-field theory with
local density approximation.Comment: Accepted in Physica B, Condensed Matte
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