A5064130022- 2D Materials and Applications
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Perovskite Materials and Applications
- Graphene research and applications
- MXene and MAX Phase Materials
- Winter Sports Injuries and Performance
- Ferroelectric and Piezoelectric Materials
- Chalcogenide Semiconductor Thin Films
- Agricultural and Food Sciences
- Porphyrin and Phthalocyanine Chemistry
- Advanced Sensor and Energy Harvesting Materials
- Urban Heat Island Mitigation
- Nuclear Receptors and Signaling
- Time Series Analysis and Forecasting
- Conducting polymers and applications
- Advanced Physical and Chemical Molecular Interactions
- Coffee research and impacts
- Thermodynamic and Structural Properties of Metals and Alloys
- Plasmonic and Surface Plasmon Research
- Noise Effects and Management
- Material Science and Thermodynamics
- Rural Development and Agriculture
- Strong Light-Matter Interactions
- Anomaly Detection Techniques and Applications
University of Minho
2005-2024
University of Coimbra
2024
University of Manchester
2021-2022
Henry Royce Institute
2021-2022
International Iberian Nanotechnology Laboratory
2019
National Institute for Space Research
2002
Abstract Twisted heterostructures of two-dimensional crystals offer almost unlimited scope for the design new metamaterials. Here we demonstrate a room temperature ferroelectric semiconductor that is assembled using mono- or few-layer MoS 2 . These van der Waals feature broken inversion symmetry, which, together with asymmetry atomic arrangement at interface two 2D crystals, enables domains alternating out-of-plane polarization arranged into twist-controlled network. The last can be moved by...
The electronic and optical properties of 2D hexagonal boron nitride are studied using first principle calculations. GW BSE methods employed in order to predict with better accuracy the excited excitonic this material. We determine values band gap, binding energies analyse wave functions. also calculate exciton following an equation motion formalism Elliot formula, find a very good agreement GW+BSE method. for both TM TE modes, showing that hBN is candidate polaritonics UV range. In...
Twistronic van der Waals heterostrutures offer exciting opportunities for engineering optoelectronic properties of nanomaterials. Here, we use multiscale modeling to study trapping charge carriers and excitons by ferroelectric polarisation piezoelectric charges domain structures in twistronic WX$_2$/MoX$_2$ bilayers (X=S,Se). For almost aligned 2H-type bilayers, find that holes electrons are trapped the opposite -- WMo XX (tungsten over molybdenum {\it versus} overlaying chalcogens) corners...
Moiré structures in small-angle-twisted bilayers of two-dimensional (2D) semiconductors with a broken-symmetry interface form arrays ferroelectric (FE) domains periodically alternating out-of-plane polarization. Here, we propose network theory for the tunability such FE domain structure by applying an electric field perpendicular to 2D crystal. Using multiscale analysis, derive fully parametrized string-theory-like description wall (DWN) and show that it undergoes qualitative change, after...
Lattice reconstruction in twisted transition-metal dichalcogenide (TMD) bilayers gives rise to piezo- and ferroelectric moir\'e potentials for electrons holes, as well a modulation of the hybridisation across bilayer. Here, we develop hybrid $\mathbf{k}\cdot \mathbf{p}$ tight-binding models describe holes relevant valleys TMD homobilayers with parallel (P) anti-parallel (AP) orientations monolayer unit cells. We apply these superlattice effects WSe${}_2$ bilayers, conjunction microscopic...
Green roof systems can contribute to sustainable urban planning in terms of acoustics by absorbing sound energy and thereby reducing levels. However, these positive contributions may vary depending on the substrate's nature, characteristics plants, extent vegetation coverage. In this work, experimental measurements were carried out both a reverberation chamber an anechoic assess effect two different substrates (an engineered substrate specifically prepared for green ordinary soil), three...
Phosphorene is a bidimensional material that has properties useful for semiconductor devices. In this work we studied the electronic and optical of using $GW$ approximation Bethe-Salpeter equation (BSE) methods. We stress importance careful convergence study most relevant parameters, show how they affect result calculations. A comparison with previous results given. The QP band gap obtained was 2.06 eV it in good agreement experimental results. BSE calculations were performed on top...
Hydrogen and hydrogen-containing gases are commonly used as reductants in chemical vapor deposition growth of MoS2. Here, we consider the defects resulting from presence hydrogen during electronically active defects. In particular, find that interstitial defect is a negative-U center with amphoteric donor acceptor properties. Additionally, effects interaction water oxygen. The analysed using density functional theory calculations.
Abstract Moiré superlattices in twistronic heterostructures are a powerful tool for materials engineering. In marginally twisted (small misalignment angle, θ ) bilayers of nearly lattice-matched two-dimensional (2D) crystals moiré patterns take the form domains commensurate stacking, separated by network domain walls (NoDW) with strain hot spots at NoDW nodes. Here, we show that, type-II transition metal dichalcogenide MoX 2 /WX (X=S, Se), hydrostatic component these creates quantum dots...
In van der Waals heterostructures, the relative alignment of bands between layers, and resulting band hybridisation, are key factors in determining a range electronic properties. This work examines these effects for heterostructures transition metal dichalcogenides (TMDs) hexagonal boron nitride (hBN), an ubiquitous combination given role hBN as encapsulating material. By comparing results density functional calculations with experimental angle-resolved photoemission spectroscopy (ARPES)...
We study the dielectric response of few layered crystals various transition metal dichalcogenides (TMDs) and hexagonal Boron Nitride (hBN). showed that out-of-plane polarizability a multilayer crystal (which characterizes to external displacement field) scales linearly with number layers, $\alpha_{zz}^{NL} =N \alpha_{zz}^{1L}$, independently stacking configuration in film. also established additivity ferroelectric polarizations consecutive interfaces case when such have broken inversion...
Regardless of the type sport, coaches must perform difficult task evaluating performance athletes. In some cases, this is aided using technology which provides tools for purpose. When sport considered taekwondo scenario does not apply as athlete evaluation methods used are mostly manual. Thus, project presented in paper has main objective to develop a system that can be tool evaluate athletes real time, with special attention low cost implementation and ease use. With intention meeting these...
Abstract In bilayers of two-dimensional semiconductors with stacking arrangements which lack inversion symmetry charge transfer between the layers due to layer-asymmetric interband hybridisation can generate a potential difference layers. We analyse transition metal dichalcogenides (TMDs)—in particular, $$\hbox {WSe}_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>WSe</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> </mml:math> —for we find substantial...
Twistronic assembly of 2D materials employs the twist angle between adjacent layers as a tuning parameter for designing electronic and optical properties van der Waals heterostructures. Here, we study how interlayer hybridization, weak ferroelectric charge transfer layers, piezoelectric response to deformations set valence conduction band edges across moir{é} supercell in twistronic homobilayers MoS$_2$, MoSe$_2$, WS$_2$ WSe$_2$. We show that, due lack inversion symmetry monolayer crystals,...
Abstract Twisted heterostructures of two-dimensional crystals offer almost unlimited scope for the design novel metamaterials. Here we demonstrate a room-temperature ferroelectric semiconductor that is assembled using mono- or few- layer MoS2. These van der Waals feature broken inversion symmetry, which, together with asymmetry atomic arrangement at interface two 2D crystals, enables domains alternating out-of-plane polarisation arranged into twist-controlled network. The latter can be moved...
This study outlines the assessment of cyber–physical system SPERTA, which was designed to evaluate real-time performance Taekwondo athletes. The conducts analyses focusing on speed, acceleration, strength, and identifying quantifying athlete’s movements. research involved administering an online questionnaire athletes coaches system’s acceptance usability. methodology included using a with open closed questions assess participant satisfaction results showed positive response system,...