Quantum Espresso : Applications for Material Sciences and Chemistry

Abstracts

10. Efficient many-body perturbation theory calculations in 2D materials: Applications to ARPES and EELS of Graphene

Andrea Ferretti (Istituto Nanoscienze)

Many-body perturbation theory methods are able to accurately predict quasiparticle (QP) and spectroscopic properties of several classes of materials. However, the calculation of the QP band structure of 2D materials is known to require a very dense BZ sampling. For 2D semiconductors, large q-point grids are required to describe the sharp q-dependence of the dielectric matrix in the...

12. Electron Spin Resonance studies from first-principles: the case of boron in silicon carbide

José Coutinho (University of Aveiro)

Despite advances toward improving the quality of 𝑝-type 4H-SiC substrates and layers, until recently we were still missing a model capable of accounting for the multitude of boron-related optical, junction, and paramagnetic resonance experiments available in the literature. A conspicuous puzzle was the observation of two shallow boron defects with rather distinct axial orientations as found by...

20. Electronic properties and defect levels induced by n/p-type defect-complexes in Ge

Emmanuel Igumbor (University of Johannesburg)

Defect-complexes are point defects that significantly influence the geometric,
optical, and electrical properties of materials. The presence of defect-complexes
in Ge have been reported to be electrically active and influence the performance of its device. Despite of this breakthrough, several defect-complexes in Ge are not well understood; hence may pose as a challenge to the optimal...

22. Electronic Structure, Optical and Thermal Properties of SrTiO3 Perovskite – A DFT+U Study

PALANI MUTHU K (MANONMANIAM SUNDARANAR UNIVERSITY)

The structural, electronic, optical, elastic, and ferroelectric characteristics of cubic strontium titanate ($SrTiO_3$) with the space group $(Pm\bar3m)$, have been computationally assessed through density functional theory (DFT). In this analysis, the Projector Augmented Wave (PAW) pseudo-potential was employed in conjunction with the Perdew Burke Ernzerhof (PBE) exchange-correlation...

17. Impressive Electronic and Thermal Transports in CsK$_2$Sb: A Thermoelectric Perspective

Dr Gautam Sharma (Khalifa University)

Over the past 2 decades, there has been active research into the
hunt for innovative thermoelectric materials with a high value of the figure of merit. To investigate the potential of CsK$_2$Sb as a thermoelectric material, we analyzed its electrical and thermal transport properties using density functional theory and Boltzmann transport theory. We found that CsK$_2$Sb is a direct band gap...

18. New Wide Bandgap Semiconductor Pentagonal CPN Monolayer: Ab initio investigation

Djamel Bezzerga (University of relizane-Algeria)

Pentagonal two-dimensional ternary monolayer represent a promising category of materials with distinctive features and a wide array of potential applications. In our work, we have utilized first-principles density functional theory (DFT) calculations using quantum espresso code to identify a novel pentagonal structure, denoted as p-CPN. This newly discovered p-CPN exhibits robust geometric,...

1. Non-covalent interactions and chemical bonding in Quantum ESPRESSO

Alberto Otero de la Roza (Universidad de Oviedo, Spain)

Quantum ESPRESSO (QE) is one of the leading software suites for materials modeling, implementing density-functional theory (DFT) in the plane-waves/pseudopotentials and projector augmented wave (PAW) approaches. Non-covalent interactions are important in materials that are weakly bound, such as molecular crystals or two-dimensional layered van der Waals solids. To describe these interactions...

16. Optical signals of qubits in defected 2D TMDs

Pedro Melo (VASP Software GmbH)

It has been shown that intrinsic properties alone cannot sustain long lived spin signals in transition metal dichalcogenides (TMDs) and that these must come from extrinsic properties[1]. Here defects play a crucial role by enriching the optical properties of a material. In this work we link different types of defects to specific optical signatures by employing many-body perturbation theory...

25. Polarons in 2D materials and in halide perovskites using the EPW code

Feliciano Giustino (The University of Texas at Austin)

The aim of this talk is twofold: First, to introduce the EPW code, a core module of the Quantum ESPRESSO materials simulation suite which specializes on high-accuracy calculations of electron-phonon interactions and related materials properties; Second, to describe some recent applications of EPW to the study of polarons in two-dimensional crystals and halide perovskites.

Since its...

2. Pushing the frontiers of Hubbard functionals: First-principles U and V in Quantum ESPRESSO

Iurii Timrov (Ecole Polytechnique Federale de Lausanne)

Density-functional theory (DFT) with extended Hubbard functionals is a powerful method for studying complex materials containing transition-metal and rare-earth elements, owing to its accuracy in correcting self-interactions and its low computational costs [1]. Recently, we developed an automated and reliable approach for the first-principles determination of the on-site U and inter-site V...

14. Strain Engineering in 2D Materials: From First Principles to Experimental Realization

Dr Jelena Pesic (Institute of Physics Belgrade, University of Belgrade)

The application of strain in 2D materials serves as a powerful tool, not only for the precise tailoring of material properties to meet specific application demands and driving the development of cutting-edge technologies but also for the advancement of our comprehension of fundamental scientific principles. It unveils the complex interplay and interdependence between material structures and...

15. Strongly anharmonic lattice vibrations and superconductivity

Ion Errea (University of the Basque Country)

In this talk I will discuss that often the standard treatment of lattice dynamics in the harmonic approximation breaks down and a non-perturbative treatment of anharmonicity is needed to describe the ionic fluctuations of the system. This occurs for instance in systems close to second-order displacive phase transitions, like ferroelectric or charge-density wave transitions, or in materials...

9. Synergistically Driven CoCr-LDH@VNiS2 as a Electrocatalyst for overall water splitting

Ms Simmy Joseph (CHARUSAT University, P.D.P.I.A.S, Anand)

Harnessing alternatives to fossil fuels persists to be a major problem for civilization. In this situation, effective earth-abundant water splitting catalysts are necessary to achieve a sustainable future. Here, using density functional theory (DFT) and a number of active sites on the surface selected to adsorb the H, OH, and OOH, we studied the effects of the electronic structures of VNiS2...

23. Using QE for evaluating Nanomaterials as Neural Nanostimulators with a focus on Magnetoelectric Nanoparticles

Prachi Kumari

In the pursuit of advanced brain-machine interfaces, the development of non-invasive techniques for stimulating neurons has garnered substantial interest. One form of such a neural stimulator is magnetoelectric nanoparticles (MENPs). A MENP made up of two-phase, spherical structure of cobalt ferrite (core) and barium titanate (shell) can convert an input magnetic field to an output electric...

3. Water splitting on transition metal oxide surfaces: insights from DFT

Ralph Gebauer (ICTP - The Abdus Salam International Centre for Theoretical Physics)

In this presentation I will show how DFT calculations can help to better understand the performance of a material as a catalyst for the water splitting reaction.
In order split water molecules into oxygen and hydrogen, two distinct half-reactions need to be catalyzed: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). I will argue that the OER is by far more...

13. Why yttrium hexaboride exhibits a much higher superconducting critical temperature than near-identical lanthanum hexaboride: a chemical bonding study under phonons

Robert Lavroff (UCLA)

Though YB6 and LaB6 share the same crystal structure, atomic valence electron configuration, and phonon modes, they exhibit drastically different phonon-mediated superconductivity. YB6 superconducts below 8.4 K, giving it the second-highest critical temperature of known borides. LaB6 does not superconduct until near-absolute zero temperatures, however. Though previous studies have quantified...