Related papers: Improving MP2 band gaps with low-scaling approxima…
A new non-perturbative framework for many-body correlated systems is formulated by extending the operator projection method (OPM). This method offers a systematic expansion which enables us to project into the low-energy structure after…
Motivated by the recently synthesized two-dimensional semiconducting MoSi$_2$N$_4$, we systematically investigate the quasiparticle band alignment and exciton in monolayer MA$_2$Z$_4$ (M = Mo, W, Ti; A= Si, Ge; Z = N, P, As) using ab initio…
Besides its predicted promising high electron mobilities at room temperature, PtSe2 bandgap sensitively depends on the number of monolayers combined by van der Waals interaction according to our calculations. We understand this by using…
We present the application of the recently developed one-body M{\o}ller--Plesset perturbation theory (OBMP2) to the prediction of K-edge excited states. OBMP2 is a self-consistent perturbation theory in which a canonical transformation…
Low-scaling electron correlation theory based on the pair natural orbital approximation, PNO-CCSD(T), has become a powerful computational tool. Motivated by the recent discovery of large errors for organometallic molecules, we assess the…
We theoretically study electronic states in graded-gap junctions of IV-VI compounds with band inversion. Using a two-band model within the ${\bf k}\cdot{\bf p}$ approximation and assuming that the gap and the gap centre present linear…
We analyze behavior of correlated electrons described by Hubbard-like models at intermediate and strong coupling. We show that with increasing interaction a pole in a generic two-particle Green function is approached. The pole signals…
We extend our approach based on the second order perturbation theory in the Coulomb interaction recently developed for quantum dots coupled to superconducting leads to the superconducting double quantum dot setups. Using our perturbative…
The $GW$ approximation to many-body perturbation theory is a reliable tool for describing charged electronic excitations, and it has been successfully applied to a wide range of extended systems for several decades using a plane-wave basis.…
A study is presented of the electronic band structure and optical absorption spectrum of monolayer WSe$_2$ using an all-electron quasiparticle self-consistent $GW$ approach, QS$G\hat W$, in which the screened Coulomb interaction $\hat W$ is…
The ability of several density-functional theory (DFT) exchange-correlation functionals to describe hydrogen bonds in small water clusters (dimer to pentamer) in their global minimum energy structures is evaluated with reference to second…
Coupled-cluster and Green's function theories are highly successful in treating many-body electron correlation, and there has been significant interest in identifying and leveraging connections between them. Here we present a diagrammatic…
MoTe2 belongs to the semiconducting transition metal dichalcogenide family with some properties differing from the other well-studied members (Mo,W)(S,Se)2. The optical band gap is in the near infrared region and both monolayers and…
Electronic Raman scattering studies on MgB2 single crystals as a function of excitation and polarization have revealed three distinct superconducting features: a clean gap below 37 cm-1 and two coherence peaks at 109 cm-1 and 78 cm-1 which…
We report on a formulation and implementation of a scheme to compute NMR shieldings at second-order Moller-Plesset (MP2) perturbation theory using gauge-including atomic orbitals (GIAOs) to ensure gauge-origin independence and Cholesky…
We analyze a data set comprising 370 GW band structures composed of 61716 quasiparticle (QP) energies of two-dimensional (2D) materials spanning 14 crystal structures and 52 elements. The data results from PAW plane wave based one-shot…
Transition-metal-based Heusler semiconductors are promising materials for a variety of applications ranging from spintronics to thermoelectricity. Employing the $GW$ approximation within the framework of the FLAPW method, we study the…
The millimeter sized monolayer and bilayer 2H-MoTe2 single crystal samples are prepared by a new mechanical exfoliation method. Based on such high-quality samples, we report the first direct electronic structure study on them, using…
We describe the relationship between the GW approximation and various equation-of-motion (EOM) coupled-cluster (CC) theories. We demonstrate the exact equivalence of the G$_0$W$_0$ approximation and the propagator theory for an…
Nowadays pseudopotential density-functional theory calculations constitute the standard approach to tackle solid-state electronic problems. These rely on distributed pseudopotential tables that were built from all-electron atomic…