A5049903688- Molecular Junctions and Nanostructures
- Quantum and electron transport phenomena
- Graphene research and applications
- Magnetic properties of thin films
- Machine Learning in Materials Science
- 2D Materials and Applications
- ZnO doping and properties
- Magnetism in coordination complexes
- Magnetic and transport properties of perovskites and related materials
- Surface and Thin Film Phenomena
- Physics of Superconductivity and Magnetism
- Electronic and Structural Properties of Oxides
- Topological Materials and Phenomena
- Advanced Chemical Physics Studies
- Organic and Molecular Conductors Research
- Electrocatalysts for Energy Conversion
- Perovskite Materials and Applications
- Electrochemical Analysis and Applications
- Advanced Condensed Matter Physics
- MXene and MAX Phase Materials
- X-ray Diffraction in Crystallography
- Semiconductor materials and devices
- Chalcogenide Semiconductor Thin Films
- Heusler alloys: electronic and magnetic properties
- Spectroscopy and Quantum Chemical Studies
Advanced Materials and BioEngineering Research
2016-2025
Trinity College Dublin
2016-2025
SRM University
2024
University of Bergamo
2024
STMicroelectronics (Italy)
2021
22q11 Ireland
2014-2020
Duke University
2013-2020
Institute of Solid State Physics
2020
Chinese Academy of Sciences
2020
University of Science and Technology of China
2020
Few layer black phosphorus is a new two-dimensional material which of great interest for applications, mainly in electronics. However, its lack stability severely limits our ability to synthesise and process this material. Here we demonstrate that high-quality, few-layer nanosheets can be produced large quantities by liquid phase exfoliation the solvent N-cyclohexyl-2-pyrrolidone (CHP). We control nanosheet dimensions have developed metrics estimate both size thickness spectroscopically....
We have studied the dispersion and exfoliation of four inorganic layered compounds, WS(2), MoS(2), MoSe(2), MoTe(2), in a range organic solvents. The aim was to explore relationship between chemical structure exfoliated nanosheets their dispersibility. Sonication compounds solvents generally gave few-layer with lateral dimensions few hundred nanometers. However, dispersed concentration varied greatly from solvent solvent. For all materials, peaked for surface energy close 70 mJ/m(2),...
Ab initio computational methods for electronic transport in nanoscaled systems are an invaluable tool the design of quantum devices. We have developed a flexible and efficient algorithm evaluating $I\text{\ensuremath{-}}V$ characteristics atomic junctions, which integrates nonequilibrium Green's function method with density functional theory. This is currently implemented package SMEAGOL. The heart SMEAGOL our scheme constructing surface functions describing current-voltage probes. It...
The hybrid halide perovskite CH$_{3}$NH$_{3}$PbI$_{3}$ has enabled solar cells to reach an efficiency of about 18\%, demonstrating a pace for improvements with no precedents in the energy arena. Despite such explosive progress, microscopic origin behind success material is still debated, role played by organic cations light-harvesting process remaining unclear. Here van-der-Waals-corrected density functional theory calculations reveal that orientation molecules plays fundamental determining...
Opening up a band gap and finding suitable substrate material are two big challenges for building graphene-based nanodevices. Using state-of-the-art hybrid density functional theory incorporating long-range dispersion corrections, we investigate the interface between optically active graphitic carbon nitride (g-C3N4) electronically graphene. We find an inhomogeneous planar promotes electron-rich hole-rich regions, i.e., forming well-defined electron–hole puddle, on supported graphene layer....
Density functional theory is used to systematically study the electronic properties of doped MoS${}_{2}$ monolayers, where dopants are incorporated both via S/Mo substitution or as adsorbates. Among possible substitutional at Mo site, Nb identified suitable $p$-type dopant, while Re donor with lowest activation energy. When simply adsorbed on a monolayer we find that alkali metals shift Fermi energy into conduction band, making system $n$ type. Finally, adsorption charged molecules...
In view of recent experimental reports unexpected ferromagnetism in HfO(2) thin films, we carried out first-principles investigations looking for magnetic order possibly brought about by the presence small concentrations intrinsic point defects. Ab initio electronic structure calculations using density functional theory show that isolated cation vacancy sites lead to formation high-spin defect states. Furthermore these appear be ferromagnetically coupled with a rather short range...
Inspired by recent experiments on the successful fabrication of monolayer Janus transition-metal dichalcogenides [Lu, A.-Y.; Nat. Nanotechnol. 2017, 12, (8), 744 and ferromagnetic VSe2 [Bonilla, M.; 2018, 13, (4), 289], we predict a highly stable room-temperature (VSSe) density functional theory methods further confirmed stability global minimum search with particle-swarm optimization method. The VSSe exhibits large valley polarization due to broken space- time-reversal symmetry. Moreover,...
Abstract The use of single molecule magnets in mainstream electronics requires their magnetic moment to be stable over long times. One can achieve such a goal by designing compounds with spin-reversal barriers exceeding room temperature, namely large uniaxial anisotropies. Such strategy, however, has been defeated several recent experiments demonstrating under-barrier relaxation at high behaviour today unexplained. Here we propose spin–phonon coupling responsible for anomaly. With...
Abstract The charge transport properties of hybrid halide perovskites are investigated with a combination density functional theory including van der Waals interaction and the Boltzmann for diffusive in relaxation time approximation. We find mobility electrons to be range 5–10 cm 2 V −1 s that holes within 1–5 , where variations depend on crystal structure level doping. Such results, good agreement recent experiments, set about 1 ps, which is time-scale molecular rotation at room...
Although transition metal dichalcogenides such as MoS2 have been recognized highly potent two-dimensional nanomaterials, general methods to chemically functionalize them are scarce. Herein, we demonstrate a functionalization route that results in organic groups bonded the surface via covalent C–S bonds. This is based on lithium intercalation, chemical exfoliation and subsequent quenching of negative charges residing by electrophiles diazonium salts. Typical degrees 10–20 atom % potentially...
Transition metal-free magnetism and half-metallicity recently has been the subject of intense research activity due to its potential in spintronics application. Here we, for first time, demonstrate via density functional theory that most experimentally realized graphitic carbon nitride (g-C4N3) displays a ferromagnetic ground state. Furthermore, this novel material is predicted possess an intrinsic never reported date. Our results highlight new promising toward realistic
We present a complete prescription for the numerical calculation of surface Green's functions and self-energies semi-infinite quasi-one-dimensional systems. Our work extends previous results generating robust algorithm to be used in conjunction with ab initio electronic structure methods. perform detailed error analysis scheme find that highest accuracy is found if no inversion usually ill conditioned hopping matrix involved. Even this case however transformation decreases its condition...
Ab-initio density functional theory calculations are performed to study the electronic properties of a MoS2 monolayer deposited over SiO2 substrate in presence interface impurities and defects. When is placed on defect-free oxide plays an insignificant role, since conduction band top valence minimum located approximately middle band-gap. However, if Na O dangling bonds introduced at surface, these lead localized states, which modulate conductivity from n- p-type. Our results show that...
Advanced computer simulations and database access enable the design of novel magnetic materials at an unprecedented speed.
Abstract Andreas Berger CICnanoGUNE BRTA Following the success and relevance of 2014 2017 Magnetism Roadmap articles, this 2020 edition takes yet another timely look at newly relevant highly active areas in magnetism research. The overall layout article is unchanged, given that it has proved most appropriate way to convey aspects today’s research a wide variety sub-fields broad readership. A different group experts again been selected for article, representing both breadth new areas, desire...
Dirac semimetals have attracted extensive attentions in recent years. It has been theoretically suggested that many-body interactions may drive exotic phase transitions, spontaneously generating a mass for the nominally massless electrons. So far, signature of interaction-driven transition lacking. In this work, we report high-magnetic-field transport measurements semimetal candidate ZrTe5. Owing to large g factor ZrTe5, Zeeman splitting can be observed at magnetic field as low 3 T. Most...
The design of slow relaxing magnetic molecules requires the optimization internal molecular vibrations to reduce spin-phonon coupling.
All density-functional calculations of single-molecule transport to date have used continuous exchange-correlation approximations. The lack derivative discontinuity in such leads the erroneous prediction metallic for insulating molecules. A simple and computationally undemanding atomic self-interaction correction (SIC) opens conduction gaps I-V characteristics that otherwise are predicted metallic, as case prototype Au/ditholated-benzene/Au junction.