Related papers: Correlation-Driven Electronic Reconstruction in Fe…
We study theoretically the electron correlation effect in a three-dimensional Dirac fermion system which describes a topologically nontrivial state. It is shown within the mean-field approximation that time-reversal and inversion symmetries…
The large anisotropy in the electronic properties across a structural transition in several correlated systems has been identified as the key manifestation of electronic nematic order, breaking rotational symmetry. In this context, FeSe is…
The role of electronic Coulomb correlations in iron-based superconductors is an important open question. We provide theoretical evidence for strong correlation effects in the FeSe compound, based on dynamical mean field calculations. A…
Here we report the first results of the high-pressure Hall coefficient (RH) measurements, combined with the high-pressure resistance measurements, at different temperatures on the putative topological superconductor FeTe0.55Se0.45. We find…
Recently, layered copper chalcogenides Cu2X family (X=S, Se, Te) has attracted tremendous research interests due to their high thermoelectric (TE) performance, which is partly due to the superionic behavior of mobile Cu ions, making these…
Strong electron-electron interaction can induce Mott insulating state, which is believed to host unusual correlated phenomena such as quantum spin liquid when quantum fluctuation dominates and unconventional superconductivity through…
Using angle-resolved photoemission spectroscopy we have studied the low-energy electronic structure and the Fermi surface topology of Fe$_{1+y}$Te$_{1-x}$Se$_x$ superconductors. Similar to the known iron pnictides we observe hole pockets at…
A number of recent experiments have highlighted a remarkable transformation of a large cuprate Fermi surface into small pockets in the underdoped region signalling a breakdown of a conventional Fermi liquid theory in the PG phase. A few…
We study the crystalline and electronic properties of the $\textrm{Fe}_{1-x}\textrm{Co}_x\textrm{Se}$ system ($x=0$, 0.25, 0.5, 0.75, and 1.0) using X-ray diffraction, X-ray spectroscopy and density functional theory. We show that the…
Using the fluctuation exchange approximation and a three-orbital model, we study the band renormalization, Fermi surface reconstruction and the superconducting pairing symmetry in the newly-discovered iron-based superconductors. We find…
The interplay between electronic orders and superconductivity is central to the physics of unconventional superconductors, and is particularly pronounced in the iron-based superconductors. Motivated by recent experiments on FeSe, we study…
Superconducting iron chalcogenide FeSe has the simplest crystal structure among all the Fe-based superconductors. Unlike other iron pnictides, FeSe exhibits no long range magnetic order accompanying the tetragonal-to-orthorhombic structural…
The layered iron superconductors are discussed using electronic structure calculations. The four families of compounds discovered so far, including Fe(Se,Te) have closely related electronic structures. The Fermi surface consists of…
We study the electronic structure of an exotic superconductor, PdTe employing depth-resolved high resolution photoemission spectroscopy and density functional theory. The valence band spectra exhibit large density of states at the Fermi…
The electronic structure and phase stability of paramagnetic FeSe is computed by using a combination of ab initio methods for calculating band structure and dynamical mean-field theory. Our results reveal a topological change (Lifshitz…
Flat electronic bands are expected to show proportionally enhanced electron correlations, which may generate a plethora of novel quantum phases and unusual low-energy excitations. They are increasingly being pursued in $d$-electron-based…
The role of electronic correlations in Condensed Matter is at the heart of various important systems, like magnetic materials, superconductors, topological materials, optical lattices, etc. Electronic correlations are those which change the…
FeSe is classed as a Hund's metal, with a multiplicity of $d$ bands near the Fermi level. Correlations in Hund's metals mostly originate from the exchange parameter \emph{J}, which can drive a strong orbital selectivity in the correlations.…
Motivated by recent developments in the study of quasi-one-dimensional iron systems with Fe$^{2+}$, we comprehensively study the Fe$^{3+}$ chalcogenide chain system. Based on first-principles calculations, the Fe$^{3+}$ chain has a similar…
Hexagonal FeSe thin films were grown on SrTiO3 substrates and the temperature and thickness dependence of their electronic structures were studied. The hexagonal FeSe is found to be metallic and electron doped, whose Fermi surface consists…