Related papers: Bond order potential for FeSi
We develop an approach to construct local bulk operators in a CFT to order $1/N^2$. Since 4-point functions are not fixed by conformal invariance we use the OPE to categorize possible forms for a bulk operator. Using previous results on…
Single crystalline FeSi samples with a conducting surface state (CSS) were studied under high pressure ($\textit{P}$) and magnetic field ($\textit{B}$) by means of electrical resistance ($\textit{R}$) measurements to explore how the bulk…
We show, from first-principles calculations, that the hole-doped side of FeAs-based compounds is different from its electron-doped counterparts. The electron side is characterized as Fermi surface nesting, and SDW-to-NM quantum critical…
Using the folding procedure, we investigate the bound state of the $\Omega$+$\alpha$ system based on $\Omega$-$N$ ($^{5}S_{2}$) HAL QCD potential. Previous theoretical analyses have indicated the existence of a deeply bound ground state,…
The structural, electronic, mechanic, vibrational and thermodynamic properties of Ti2SiB which is a hypothetical MAX phase compound, have been investigated using density functional theory calculations. The structural optimization of Ti2SiB…
Born effective charge (BEC), a fundamental quantity in lattice dynamics and ferroelectric theory, provides a quantitative measure of linear polarization response to ionic displacements. However, it does not account for higher-order effects,…
The finite basis optimized effective potential (OEP) method within density functional theory is examined as an ill-posed problem. It is shown that the generation of nonphysical potentials is a controllable manifestation of the use of…
We address two important issues that arise in recent studies of iron-based superconductivity. (1) Why are the T_c of A_xFe_{2-y}Se_2 and the single unit cell FeSe on SrTiO$_3$ so high despite both only have electron pockets? (2) What (if…
Strong correlations lead to emergent excitations at low energies. When combined with symmetry constraints, they may produce topological electronic states near the Fermi energy. Within this general framework, here we address the topological…
Charge modulations are considered as a leading competitor of high-temperature superconductivity in the underdoped cuprates, and their relationship to Fermi surface reconstructions and to the pseudogap state is an important subject of…
We analyze superconductivity in a multi-orbital fermionic system near the onset of a nematic order, using doped FeSe as an example. We associate the nematic order with spontaneous polarization between $d_{xz}$ and $d_{yz}$ orbitals. We…
We describe a general method to model multicomponent ordered crystals using the phase-field crystal (PFC) formalism. As a test case, a generic B2 compound is investigated. We are able to produce a line of either first-order or second-order…
In high-superconducting transition temperature ($T_{\rm c}$) iron-based superconductors, interband sign reversal ($s_{\rm \pm}$) and sign preserving ($s_{\rm ++}$) $s$-wave superconducting states have been primarily discussed as the…
We report density functional theory (DFT) investigation of $B$-site doped CaFeO$_3$, a prototypical charge-ordered perovskite. At 290 K, CaFeO$_3$ undergoes a metal-insulator transition and a charge disproportionation reaction…
Films of all-important compound hafnia (HfO2) can be prepared in an orthorhombic ferroelectric (FE) state that is ideal for applications, e.g. in memories or negative-capacitance field-effect transistors. The origin of this FE state remains…
We studied the relationship between the charge doping and the correlation, and its effects on the spectral function of the BaFe$_2$As$_2$ compound in the framework of the density functional theory combined with the dynamical mean field…
We study the magnetic Compton profile (MCP) of the disordered Fe$_{0.5}$Ni$_{0.5}$ and of the ordered FeNi alloys and discuss the interplay between structural disorder and electronic correlations. The Coherent Potential Approximation is…
Motivated by the recent ARPES measurements (Evtushinsky et. al., PRL {\bf 105}, 147201 (2010)) and evidence for the density-wave state for the charge and orbital ordering (Garc\'{i}a et al., PRL {\bf 109}, 107202 (2012)) in…
We investigate the critical properties of the phase transition towards complex tensor order that has been proposed to occur in spin-orbit coupled superconductors. For this purpose we formulate the bosonic field theory for fluctuations of…
We develop in detail a model of the charge order in NbSe$_2$ deriving from a strong electron-phonon coupling dependent on the ingoing and outgoing electron momenta as well as the electronic orbitals scattered between. Including both…