Article
Materials Science, Multidisciplinary
Frank T. Cerasoli, Andrew R. Supka, Anooja Jayaraj, Marcio Costa, Ilaria Siloi, Jagoda Slawinska, Stefano Curtarolo, Marco Fornari, Davide Ceresoli, Marco Buongiorno Nardelli
Summary: PAOFLOW is a software tool that constructs tight-binding Hamiltonians from electronic wavefunctions by projecting onto atomic orbitals, providing numerous materials properties and performance improvements. The latest version includes symmetry operations, internal projection routines, non-constant relaxation time models, and real space atomic orbitals generation.
COMPUTATIONAL MATERIALS SCIENCE
(2021)
Article
Multidisciplinary Sciences
Qiangqiang Gu, Linfeng Zhang, Ji Feng
Summary: The introduced neural network representation effectively predicts the electronic structure of crystalline materials based on first-principles, coupled with machine learning molecular dynamics for efficient and accurate electronic evolution and sampling; this method can calculate the spectral function and optical conductivity of one-dimensional charge-density wave materials, revealing certain physical properties of specific processes.
Article
Computer Science, Interdisciplinary Applications
Nariman Abu el Kher, Israa Zeid, Nayla El-Kork, Mahmoud Korek
Summary: The electronic structure of alkaline-earth metal hydride cations SrH+ and BaH+ have been studied, with various spectroscopic parameters and rovibrational constants determined.
These substances play a crucial role in the absorption spectrum of the sun, making theoretical studies on them essential.
JOURNAL OF COMPUTATIONAL SCIENCE
(2021)
Article
Chemistry, Physical
Mohammad Khear Sabra, Fatemh Maksoud
Summary: The study focused on cis boron hydrogen chains, investigating the ground-state energies, binding energies, Mulliken population, and optimal geometrical configurations in relation to chain size n. It was found that the chain dimerization process led to two phases - cis-transoid and trans-cisoid - with corresponding energy gaps around 0.12 eV and 0.11 eV, respectively, as determined by a modified Su-Schrieffer-Heeger (SSH) model.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Ben Shpiro, Marcel David Fabian, Eran Rabani, Roi Baer
Summary: In this paper, we develop a formalism for calculating forces on the nuclei within a nonorthogonal atom-centered basis set representation and apply it to a peptide solvated in water. We use an embedded-fragment approach to reduce statistical errors and find that the systematic bias is sufficiently small when using 120 stochastic orbitals.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Hyeri Yoo, Kyeong-Seok Lee, Sahn Nahm, Gyu Weon Hwang, Sangtae Kim
Summary: The study investigates the impact of ligand chemistry and coverage on InP surface properties using density functional theory calculations, revealing that different ligands result in different crystal shapes and surface states are altered upon ligand adsorption.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Jia-Jia Yang, Xiang-Yang Liu, Zi-Wen Li, Thomas Frauenheim, ChiYung Yam, Wei-Hai Fang, Ganglong Cui
Summary: In this study, collinear and noncollinear DFT methods were used to investigate the interfacial properties between fullerenes and the MAPbI(3) surface. The research revealed differences in the electron transfer process between different fullerenes, providing insights for enhancing the efficiency of solar cells.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Computer Science, Interdisciplinary Applications
Gan Jin, Hongsheng Pang, Yuyang Ji, Zujian Dai, Lixin He
Summary: We present PYATB, a Python package for computing band structures and related properties of materials using the ab initio tight-binding Hamiltonian. It comprises three modules: Bands, Geometric, and Optical. The Bands module enables calculation of essential properties of band structures, while the Geometric module computes Berry phase and related quantities, and the Optical module offers a range of optical property calculations.
COMPUTER PHYSICS COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Juan J. J. Aucar, Alejandro F. F. Maldonado, Juan I. I. Melo
Summary: In this work, relativistic corrections to the electric field gradient (EFG) are presented, including spin-dependent corrections for the first time. The results show that these new corrections significantly improve the performance of the existing method and are in close agreement with calculations at the four-component Dirac-Hartree-Fock (4c-DHF) level. The accuracy of the EFG values obtained with this new method allows for the analysis of the electronic origin of relativistic effects using well-known nonrelativistic operators.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
A. Amudhavalli, R. Rajeswarapalanichamy, R. Padmavathy, M. Manikandan, M. Santhosh, K. Iyakutti
Summary: The electronic structure, elastic, optical, and thermal properties of chalcopyrite solar cell compounds were systematically studied, showing their potential as effective candidates for solar cell devices. The materials displayed direct band gap semiconducting behavior and were found to be dynamically stable, with calculated lattice constants in good agreement with existing data. Additionally, the energy band gap was observed to increase with gallium concentration, indicating the possibility of tuning the properties for specific applications.
MATERIALS TODAY COMMUNICATIONS
(2021)
Article
Optics
Xiaoyan Cao, Michael Dolg
Summary: The electronic structure and luminescent properties of a strongly luminescent and highly oxygen-sensitive Tb(III) complex were studied. The mechanism of luminescence quenching in the presence of oxygen was analyzed, revealing that energy transfer to oxygen after initial photoexcitation of the ligand leads to luminescence quenching. Comparisons with a similar Sm(III) complex showed differences in luminescence quantum yield and oxygen quenching behavior.
JOURNAL OF LUMINESCENCE
(2022)
Article
Materials Science, Multidisciplinary
Te-Huan Liu, Jiawei Zhou, Qian Xu, Xin Qian, Bai Song, Ronggui Yang
Summary: The study shows that long-range electron-phonon interaction can significantly suppress thermal conductivity in certain polar semiconductors by scattering acoustic phonons. The breaking of centrosymmetry has different effects on phonon transport in different crystal structures.
MATERIALS TODAY PHYSICS
(2022)
Article
Chemistry, Physical
Jing Shang, Congxin Xia, Chun Tang, Chun Li, Yandong Ma, Yuantong Gu, Liangzhi Kou
Summary: The bending deformation of AgBiP2Se6 monolayers can manipulate the polarization direction and domain size, significantly improving the ferroelectric stability. This mechano-ferroelectric coupling represents a new mechanism for stabilization and polarization flip in 2D ferroelectrics, with potential applications in next-generation non-volatile storage devices.
NANOSCALE HORIZONS
(2021)
Article
Green & Sustainable Science & Technology
Yiran Li, Mengling Lai, Minmin Hu, Shijun Zhao, Bin Liu, Ji-Jung Kai
Summary: This review summarizes the current understanding of the electronic and magnetic properties of two-dimensional (2D) transition metal carbides and/or nitrides (MXenes) from the perspectives of chemical compositions and structural configurations. The potential band-structure modifications and electronic applications of MXenes are emphasized. MXenes, as an important member of post-graphene 2D materials, are still under-explored but have shown promising electronic and magnetic properties.
SUSTAINABLE MATERIALS AND TECHNOLOGIES
(2022)
Article
Engineering, Electrical & Electronic
F. Djali, T. Ouahrani, S. Hiadsi, M. R. Boufatah
Summary: This study presents the first attempt to investigate the thermoelectric properties of FeZrTe half-Heusler alloy through theoretical calculations. The phonon dispersion and crystal structures are obtained using density functional theory and finite displacement method. The results show that FeZrTe alloy is mechanically and dynamically stable in its type I structure, and has a semiconducting character with a band gap of 1.4 eV. The variations of thermoelectric properties with carrier concentration and temperature have been studied, indicating the potential for constructing an n-p couple for a thermoelectric device.
JOURNAL OF ELECTRONIC MATERIALS
(2023)
Article
Physics, Multidisciplinary
Sofia Sanz, Nick Papior, Geza Giedke, Daniel Sanchez-Portal, Mads Brandbyge, Thomas Frederiksen
Summary: This study investigated structures composed of narrow zigzag graphene nanoribbons (GNRs) and found that the beam-splitting effect can survive under Coulomb repulsion and a spin-dependent scattering potential can emerge. The researchers also discovered that this is a general feature with edge-polarized nanoribbons, and near-perfect polarization can be achieved by joining several junctions in series.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Fei Gao, Dongzhe Li, Cyrille Barreteau, Mads Brandbyge
Summary: All-electrical writing and reading of spin states can be achieved in molecular spinterfaces by depositing FeTPP molecules, and a feasible three-terminal setup to probe the spin state is proposed. In addition, we demonstrate how FeTPP modifies the quantum transport of non-spin polarized BG.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Alfred J. H. Jones, Lene Gammelgaard, Mikkel O. Sauer, Deepnarayan Biswas, Roland J. Koch, Chris Jozwiak, Eli Rotenberg, Aaron Bostwick, Kenji Watanabe, Takashi Taniguchi, Cory R. . Dean, Antti-Pekka Jauho, Peter Boggild, Thomas G. Pedersen, Bjarke S. Jessen, Soren Ulstrup
Summary: This work demonstrates the controllable induction of massive Dirac fermions in a graphene device by lithographically patterning superstructures of nanoscale holes. The band dispersion of these fermions is visualized using angle-resolved photoemission spectroscopy with nanoscale spatial resolution, showing a linear scaling of effective mass with feature sizes. Electrostatic doping enhances the effective hole mass and leads to the observation of an electronic band gap, which is strongly renormalized by carrier-induced screening. This methodology allows for the engineering of band structures of massive Dirac quasiparticles at the nanoscale.
Article
Chemistry, Multidisciplinary
Mehdi Bouatou, Cyril Chacon, Aleksander Bach Lorentzen, Huu Thoai Ngo, Yann Girard, Vincent Repain, Amandine Bellec, Sylvie Rousset, Mads Brandbyge, Yannick J. Dappe, Jerome Lagoute
Summary: This study demonstrates the realization of nanopatterning of nitrogen dopants in graphene by using a submonolayer of self-assembled physisorbed molecules as a resist during post-synthesis nitrogen doping process. The resulting domains with different nitrogen concentrations enable the formation of n-n' and p-n junctions in graphene. The electronic properties of the junctions were measured at the atomic scale using scanning tunneling microscopy, revealing an intrinsic width of approximately 7 nm corresponding to a sharp junction regime.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Physics, Multidisciplinary
Yu Zhang, Fei Gao, Shiwu Gao, Mads Brandbyge, Lin He
Summary: This study successfully visualizes and controls the intervalley scattering induced by an individual monovacancy in graphene using a scanning tunneling microscope. The research finds that the affected range of intervalley scattering is inversely proportional to the energy and observes a giant electron-hole asymmetry. By further charging the monovacancy, the scattering potential is softened and the intervalley scattering is suppressed.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Liangguang Jia, Fei Gao, Yu Zhang, Yaoyao Chen, Baofei Hou, Zeping Huang, Quanzhen Zhang, Xu Wu, Liwei Liu, Shiwu Gao, Mads Brandbyge, Hong-Jun Gao, Yeliang Wang
Summary: This study reports the influence of defects in vdW crystals on the local atomic configurations and interlayer coupling. The findings show that Se vacancies in few-layer NbSe2 can cause atomic distortions and generate in-gap states in single-layer NbSe2. Moreover, these vacancies lead to a significant suppression of interlayer coupling in the bilayer system.
Article
Physics, Condensed Matter
Sofia Sanz, Nick Papior, Geza Giedke, Daniel Sanchez-Portal, Mads Brandbyge, Thomas Frederiksen
Summary: We theoretically study electron interference in a Mach-Zehnder-like geometry formed by four parallel pairs of zigzag graphene nanoribbons. By adjusting the interribbon separation, each intersection can function as an electron beam splitter or mirror, allowing for tuneable circuitry with interfering pathways. We evaluate the electron transport properties of these eight-terminal devices and identify pairs of terminals subject to self-interference. The proposed devices have potential applications as magnetic field sensors, detectors of phase shifts induced by local scatterers, and for the study of quantum entanglement.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Multidisciplinary
Cesar Moreno, Xabier Diaz de Cerio, Manuel Vilas-Varela, Maria Tenorio, Ane Sarasola, Mads Brandbyge, Diego Pena, Aran Garcia-Lekue, Aitor Mugarza
Summary: Recent advances in surface-assisted synthesis have demonstrated the ability to create highly anisotropic nanoporous graphene structures by laterally coupling arrays of nanometer wide graphene nanoribbons. In this study, a new nanoporous graphene structure was synthesized in which the interribbon electronic coupling can be controlled by phenylene bridges. The versatility of this structure arises from the multiple configurations of phenylene cross-coupling and the twist angle, which can be altered by interaction with the substrate and other external stimuli.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Physics, Multidisciplinary
Xiaocui Wu, Nicolas Neel, Mads Brandbyge, Joerg Kroeger
Summary: The abstraction of pyrrolic hydrogen from a single phthalocyanine on graphene turns the molecule into a sensitive probe for graphene phonons. The inelastic electron transport measured with a scanning tunneling microscope across the molecular adsorbate and graphene becomes strongly enhanced for a graphene out-of-plane acoustic phonon mode. Supporting density functional and transport calculations elucidate the underlying physical mechanism.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Multidisciplinary
Fei Gao, Rodrigo E. E. Menchon, Aran Garcia-Lekue, Mads Brandbyge
Summary: Recently, researchers have combined porphyrin units with graphene nanoribbons (Por-GNR) to create various structures. In this study, the authors use first-principles calculations to investigate the properties of two experimentally feasible Por-GNR hybrids. They find that one of the hybrids has a small band gap and can be used as electrodes in devices. By embedding a Fe atom in the porphyrin, a spin-polarized ground state is achieved. The authors examine the spin transport properties of a 2-terminal setup involving a Fe-Por-GNR between Por-GNR electrodes and observe a Fano anti-resonance feature. They also demonstrate how mechanical strain or chemical adsorption can induce spin-crossover, leading to different spin states. These findings provide valuable insights for the development of carbon-based spintronics and chemical sensing applications.
COMMUNICATIONS PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Aleksander Bach Lorentzen, Mehdi Bouatou, Cyril Chacon, Yannick J. Dappe, Jerome Lagoute, Mads Brandbyge
Summary: Recent studies have shown the spatial control of nitrogen dopant concentration in graphene using a molecular mask. This technique enables the creation of ballistic electron optics-like structures and has implications for current focusing and quantized conductance.
Article
Materials Science, Multidisciplinary
Victor Rosendal, Walber H. Brito, Milan Radovic, Alla Chikina, Mads Brandbyge, Nini Pryds, Dirch H. Petersen
Summary: This study maps the energy landscape of octahedral tilting in Strontium niobate using density functional theory calculations, and finds that compressive strain induces tilting around the out-of-plane axis, while tensile strain induces tilting around the in-plane axes. The competition between in-phase and out-of-phase tilting in SrNbO3 allows for tuning the thermoelectric and optical properties. The study also shows how the tilt angle and mode affect the Seebeck coefficient and the plasma frequency due to changes in the band structure.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Cesar Moreno, Xabier Diaz de Cerio, Manuel Vilas-Varela, Maria Tenorio, Ane Sarasola, Mads Brandbyge, Diego Pena, Aran Garcia-Lekue, Aitor Mugarza
Summary: Recent advances in surface-assisted synthesis have shown that graphene nanoribbons can be coupled laterally to form nanoporous graphene structures. This graphene nanoarchitecture consists of weakly coupled semiconducting nanochannels with electron propagation characterized by interchannel quantum interferences. By utilizing phenylene bridges, the electronic coupling between the nanoribbons in the nanoporous graphene structure can be controlled, providing versatility through different phenylene cross-coupling configurations and twist angles. Simulation results demonstrate the ability to switch on/off or modulate the interribbon coupling using the chemical or conformational knob. Molecular bridges offer efficient tools for engineering quantum transport and anisotropy in carbon-based 2D nanoarchitectures.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Materials Science, Multidisciplinary
Carlos Ortega-Taberner, Antti-Pekka Jauho, Jens Paaske
Summary: Josephson junction based on quantum dots with local gates offers convenient tunability. In this study, a Josephson junction based on a serial double quantum dot gated by phase-shifted microwave tones is analyzed. The current-phase relation of the junction is modified by the phase shift between the drives. Breaking particle-hole symmetry on the dots results in a finite average anomalous Josephson current with zero phase bias. This microwave gated weak link realizes a tunable Floquet v0 junction with maximum critical current achieved slightly off resonance with the subgap excitation energy.
Article
Materials Science, Multidisciplinary
N. Papior, S. Leitherer, M. Brandbyge
Summary: A simple, first-principles scheme for calculating current-induced stresses in bulk systems is presented, using an ideal ballistic distribution function for the electronic states. The theory is illustrated and results for 1D metal chains are provided, showing the dependence of ultimate tensile strength on the applied voltage.
