A5090558562- Graphene research and applications
- Quantum and electron transport phenomena
- Topological Materials and Phenomena
- 2D Materials and Applications
- Magnetic properties of thin films
- Advanced Memory and Neural Computing
- Carbon Nanotubes in Composites
- Magnetic Field Sensors Techniques
- Advanced Physical and Chemical Molecular Interactions
- Metamaterials and Metasurfaces Applications
- Physics of Superconductivity and Magnetism
- Surface and Thin Film Phenomena
- Atomic and Subatomic Physics Research
- Multiferroics and related materials
- Quantum chaos and dynamical systems
- Perovskite Materials and Applications
- Machine Learning in Materials Science
- Quantum many-body systems
- Geophysical and Geoelectrical Methods
- Composite Material Mechanics
- Advancements in Semiconductor Devices and Circuit Design
- Magnetic and transport properties of perovskites and related materials
- Advanced Mathematical Modeling in Engineering
- Quantum Computing Algorithms and Architecture
- Modular Robots and Swarm Intelligence
Institut Català de Nanociència i Nanotecnologia
2016-2025
Consejo Superior de Investigaciones Científicas
2018-2024
ORCID
2021
Universidade Estadual Paulista (Unesp)
2016
Universidade Federal do Rio de Janeiro
2014-2015
Graphene is an excellent material for long-distance spin transport but allows little manipulation. Transition-metal dichalcogenides imprint their strong spin–orbit coupling into graphene via the proximity effect, and it has been predicted that efficient spin-to-charge conversion due to Hall Rashba–Edelstein effects could be achieved. Here, by combining probes with ferromagnetic electrodes, we unambiguously demonstrate experimentally effect in induced MoS2 varying temperatures up room...
We report on fundamental aspects of spin dynamics in heterostructures graphene and transition metal dichalcogenides (TMDCs). By using realistic models derived from first principles we compute the lifetime anisotropy, defined as ratio lifetimes for spins pointing out plane to those plane. find that anisotropy can reach values tens hundreds, which is unprecedented typical 2D systems with spin-orbit coupling indicates a qualitatively new regime relaxation. This behavior mediated by spin-valley...
Large spin-orbital proximity effects have been predicted in graphene interfaced with a transition metal dichalcogenide layer. Whereas clear evidence for an enhanced spin-orbit coupling has found at large carrier densities, the type of and its relaxation mechanism remained unknown. We show first time increased close to charge neutrality point graphene, where topological states are expected appear. Single layer encapsulated between WSe$_2$ hBN is exhibit exceptional quality mobilities as high...
We describe an efficient numerical approach to calculate the longitudinal and transverse Kubo conductivities of large systems using Bastin's formulation. expand Green's functions in terms Chebyshev polynomials compute conductivity tensor for any temperature chemical potential a single step. To illustrate power generality approach, we quantum Hall effect disordered graphene analyze disorder Chern insulator Haldane's model on honeycomb lattice.
We report on a theoretical study of the spin Hall Effect (SHE) and weak antilocal-ization (WAL) in graphene/transition metal dichalcogenide (TMDC) heterostructures, computed through efficient real-space quantum transport methods, using realistic tight-binding models parametrized from ab initio calculations. The graphene/WS 2 system is found to maximize proximity effects compared graphene MoS , WSe or MoSe with crucial role played by disorder, given disappearance SHE signals presence strong...
In recent years, predictive computational modeling has become a cornerstone for the study of fundamental electronic, optical, and thermal properties in complex forms condensed matter, including Dirac topological materials. The simulation quantum transport realistic models calls development linear scaling, or order-N, numerical methods, which then enabling tools guiding experimental research supporting interpretation measurements. this review, we describe compare different order-N methods...
We report an unconventional quantum spin Hall phase in the monolayer T$_\text{d}$-WTe$_2$, which exhibits hitherto unknown features other topological materials. The low-symmetry of structure induces a canted texture $yz$ plane, dictates polarization topologically protected boundary states. Additionally, conductivity gets quantized ($2e^2/h$) with quantization axis parallel to canting direction. These findings are based on large-scale simulations tensor and nonlocal resistances multi-probe...
We investigate a generalized multiorbital tight-binding model on triangular lattice, system prevalent in wide range of two-dimensional materials and particularly relevant for simulating transition metal dichalcogenide monolayers. show that the interplay between spin-orbit coupling different symmetry-breaking mechanisms leads to emergence four distinct topological phases [Eck et al., Phys. Rev. B 107, 115130 (2023)]. Remarkably, this also triggers orbital Hall effect with distinguished...
We report a theoretical description of novel spin-orbit torque components emerging in two-dimensional Dirac materials with broken inversion symmetry. In contrast to usual metallic interfaces where fieldlike and dampinglike are competing, we find that an intrinsic which derives from all Fermi-sea electrons can be simultaneously enhanced along the component. Additionally, hitherto overlooked unique emerge coupling between spin pseudospin angular momenta, leading spin-pseudospin entanglement....
We report on the possibility to simultaneously generate in graphene a bulk valley-polarized dissipative transport and quantum valley Hall effect by combining strain-induced gauge fields real magnetic fields. Such unique phenomenon results from 'resonance/anti-resonance' driven superposition/cancellation of superimposed which differently affect time reversal symmetry. The onset current concomitant flow opposite is revealed conductivity plateau. employ efficient linear scaling Kubo methods...
The interconversion between spin and charge degrees of freedom offers incredible potential for spintronic devices, opening routes injection, detection, manipulation alternative to the use ferromagnets. understanding control such mechanisms, which rely on spin–orbit coupling, is therefore an exciting prospect. emergence van der Waals materials possessing large coupling (such as transition metal dichalcogenides or topological insulators) and/or recently discovered layered ferromagnets further...
Abstract Proximity effects between layered materials trigger a plethora of novel and exotic quantum transport phenomena. Besides, the capability to modulate nature strength proximity by changing crystalline interfacial symmetries offers vast playground optimize physical properties relevance for innovative applications. In this work, we use large-scale first principles calculations demonstrate that strain twist-angle strongly vary spin–orbit coupling (SOC) in graphene/transition metal...
Abstract Fundamental research on two-dimensional (2D) magnetic systems based van der Waals materials has been gaining traction rapidly since their recent discovery. With the increase of knowledge, it become clear that such have also a strong potential for applications in devices combine magnetism with electronics, optics, and nanomechanics. Nonetheless, many challenges still lay ahead. Several fundamental aspects 2D are unknown or poorly understood, as often-complicated electronic structure,...
Materials science has traditionally relied on a combination of experimental techniques and theoretical modeling to discover develop new materials with desired properties. However, these processes can be time‐consuming, resource‐intensive, often limited by the complexity material systems. The advent artificial intelligence (AI), particularly machine learning, revolutionized offering powerful tools accelerate discovery, design, characterization novel materials. AI not only enhances predictive...
Realizations of some topological phases in two-dimensional systems rely on the challenge jointly incorporating spin-orbit and magnetic exchange interactions. Here, we predict formation control a fully valley-polarized quantum anomalous Hall effect bilayer graphene, by separately imprinting proximity effects different layers. This results varying spin splittings for conduction valence bands, which gives rise to gap at single Dirac cone. The phase can be controlled gate voltage switched...
We report on the emergence of bulk, valley-polarized currents in graphene-based devices, driven by spatially varying regions broken sublattice symmetry, and revealed non-local resistance ($R_\mathrm{NL}$) fingerprints. By using a combination quantum transport formalisms, giving access to bulk properties as well multi-terminal device responses, presence non-uniform local bandgap is shown give rise valley-dependent scattering finite Fermi surface contribution valley Hall conductivity, related...
The recent observation (Gorbachev et al 2014 Science 346 448) of nonlocal resistance RNL near the Dirac point (DP) multiterminal graphene on aligned hexagonal-boron nitride (G/hBN) has been interpreted as consequence topological valley Hall currents carried by Fermi sea states just beneath bulk gap Eg induced inversion symmetry breaking. However, corresponding conductivity , quantized inside Eg, is not directly measurable. Conversely, Landauer–Büttiker formula, a numerically exact approach...
The spin polarization induced by the Hall effect (SHE) in thin films typically points out of plane. This is rooted on specific symmetries traditionally studied systems, not a fundamental constraint. Recently, experiments few-layer ${\mathrm{MoTe}}_{2}$ and ${\mathrm{WTe}}_{2}$ showed that reduced symmetry these strong spin-orbit coupling materials enables new form canted effect, characterized concurrent in-plane out-of-plane polarizations. Here, through quantum transport calculations...
We consider an effective model for graphene with interface-induced spin-orbit coupling and calculate the quantum Hall effect in low-energy limit. perform a systematic analysis of contribution different terms Hamiltonian to (QHE). By analyzing spin splitting states as function magnetic field gate voltage, we obtain scaling laws that can be used characterize experiments. Furthermore, employ real-space transport approach conductivity investigate robustness QHE disorder introduced by hydrogen...
Improved fabrication techniques have enabled the possibility of ballistic transport and unprecedented spin manipulation in ultraclean graphene devices. Spin is typically probed a nonlocal valve analyzed using diffusion theory, but this theory not necessarily applicable when charge becomes or length exceptionally long. Here, we study these regimes by performing quantum simulations valves. We find that conventional fails to capture crossover regime as well limit long length. show latter can be...
We theoretically predict that vanadium-based Janus dichalcogenide monolayers constitute an ideal platform for spin-orbit-torque memories. Using first principles calculations, we demonstrate magnetic exchange and anisotropy energies are higher heavier chalcogen atoms, while the broken inversion symmetry in form leads to emergence of Rashba-like spin-orbit coupling. The torque efficiency is evaluated using optimized quantum transport methodology found be comparable heavy nonmagnetic metals....