A5032602628- Advanced Chemical Physics Studies
- Quantum, superfluid, helium dynamics
- Cold Atom Physics and Bose-Einstein Condensates
- Electron and X-Ray Spectroscopy Techniques
- Surface and Thin Film Phenomena
- Spectroscopy and Quantum Chemical Studies
- Catalytic Processes in Materials Science
- nanoparticles nucleation surface interactions
- Quantum and electron transport phenomena
- Atomic and Molecular Physics
- Molecular Junctions and Nanostructures
- Atomic and Subatomic Physics Research
- Gold and Silver Nanoparticles Synthesis and Applications
- Physics of Superconductivity and Magnetism
- Advanced Physical and Chemical Molecular Interactions
- Quantum Electrodynamics and Casimir Effect
- Advanced Electron Microscopy Techniques and Applications
- Advanced Thermodynamics and Statistical Mechanics
- Spectroscopy and Laser Applications
- Organic and Molecular Conductors Research
- Magnetism in coordination complexes
- Ion-surface interactions and analysis
- Advanced Condensed Matter Physics
- Plasmonic and Surface Plasmon Research
- Laser-Matter Interactions and Applications
Institute of Physics
2012-2023
Donostia International Physics Center
2002-2015
Ikerbasque
2015
University of the Basque Country
2015
Commonwealth Scientific and Industrial Research Organisation
2010
Institute of High Performance Computing
2010
Technical University of Munich
1995-2004
Hokkaido University
2004
The Abdus Salam International Centre for Theoretical Physics (ICTP)
1986-2003
Rutgers, The State University of New Jersey
1993-1999
The electronic spectra of CO chemisorbed on transition metals and copper as obtained with photoelectron spectroscopies, surface Penning spectroscopy, inverse photoemission x-ray absorption spectroscopy are discussed in regard to inherent features pointing the existence a 2${\ensuremath{\pi}}^{\mathrm{*}}$--derived resonance these adsorption systems. Since various spectroscopies probe CO-metal systems predominantly excited final state, one same line, however, also affected by differences...
The dimer Mott insulator $\ensuremath{\kappa}\ensuremath{-}(\text{BEDT-TTF}{)}_{2}{\mathrm{Cu}}_{2}(\mathrm{CN}{)}_{3}$ exhibits unusual electrodynamic properties. Numerical investigations of the electronic ground state and molecular lattice vibrations reveal importance ${\mathrm{Cu}}_{2}(\mathrm{CN}{)}_{3}{}^{\ensuremath{-}}$ anion network coupled to bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) molecules: threefold cyanide coordination copper linkage isomerism in structure cause a loss...
Photons can excite collective and single-particle excitations in metals; the plasmonic are of keen interest physics, chemistry, optics, nanotechnology because they enhance coupling electromagnetic energy drive nonlinear processes electronic materials, particularly where their dielectric function $ϵ(\ensuremath{\omega})$ approaches zero. We investigate angle-resolved two-photon photoemission (2PP) spectroscopy Ag(111) surface through near-zero region. In addition to Einsteinian photoemission,...
Since the earliest implementations of various GW approximations and cumulant expansion in calculations quasiparticle propagators spectra, several attempts have been made to combine advantageous properties results these two theoretical approaches. While plus approach has proven successful interpreting photoemission spectroscopy data solids, formal connection between methods not investigated detail. By introducing a general bijective integral representation cumulants, we can rigorously...
We investigate the evolution of attosecond to femtosecond screening and emergent potentials that govern dynamics energetics electrons holes excited in various stages multiphoton photoemission processes control photoelectron yield recently reported experiments [X. Cui, C. Wang, A. Argondizzo, S. Garrett-Roe, B. Gumhalter, H. Petek, Nat. Phys. 10, 505 (2014)]. The study is focused on dynamical created preexistent quasi-two-dimensional Shockley state bands Ag(111) Cu(111) surfaces intermediate...
The Mott insulator $\ensuremath{\kappa}\ensuremath{-}{(\mathrm{BEDT}\ensuremath{-}\mathrm{TTF})}_{2}{\mathrm{Ag}}_{2}{(\mathrm{CN})}_{3}$ forms a highly-frustrated triangular lattice of $S=1/2$ dimers with possible quantum-spin-liquid state. Our experimental and numerical studies reveal the emergence slight charge imbalance between crystallographically inequivalent sites, relaxor dielectric response, hopping dc transport. In broader perspective we conclude that universal properties...
Optical fields interacting with solids excite single particle quantum transitions and elicit collective screening responses that define their penetration, absorption, reflection. The interplay of these interactions on the attosecond time scale defines how optical energy transforms to electronic, setting limits efficiency for processes such as solar harvesting or photocatalysis. Our understanding light–matter is primarily based specifying electronic structure initial particles occupying...
Using inelastic scattering of thermal energy He atoms we have determined the phonon dispersion curves in commensurate $(\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3})R30\ifmmode^\circ\else\textdegree\fi{}$ Xe monolayers adsorbed on Cu(111). In addition to well known transverse acoustic mode curve longitudinally polarized branch could be measured. Since this is first case where a finite zone-center gap (here $0.4\ifmmode\pm\else\textpm\fi{}0.15\mathrm{meV}$) has been seen for...
We consider some recently developed schemes for treating van der Waals interactions within the density functional theory (DFT) on widely discussed example of adsorption Xe Cu(111) and Pt(111) surfaces. Consistent with overall weakness surface Xe-Xe we assess performance that are appropriate to systems consisting nearly isolated fragments in which coefficients expansion deduced from DFT calculations. Such generalized calculations potential energy surfaces yield structure adlayers good...
The pronounced asymmetric broadening in the core level photoemission spectra of chemisorbed atoms is explained terms intra- and extra-atomic relaxation a qualitative comparison made with similar effect due to dynamic screening processes.
The relevance of van der Waals interactions in the scattering neutral atoms from adsorbates has been recently confirmed by highly sensitive molecular-beam techniques. theoretical descriptions collision dynamics which followed experimental studies have necessitated very careful qualitative and quantitative examinations evaluations properties atom-adsorbate for specific systems. In this work we present a microscopic calculation strengths reference-plane positions potentials relevant He CO...
Asymmetric broadening and relaxation shifts observed in the photoelectron spectra from adsorbate core levels are explained terms of intra-atomic extra-atomic effects. A simple model is set up which creation a hole an level photoemission followed by pulls valence resonant states downward towards larger binding energies. It shown that response system to this perturbation involves singular shake-up charge-transfer processes give rise drastic redistribution spectral weight state. In addition we...
Density functional theory (DFT) has been steadily improving over the past few decades, becoming standard tool for electronic structure calculations. The early local functionals (LDA) were eventually replaced by more accurate semilocal (GGA) which are in use today. A major persisting drawback is lack of nonlocal correlation at core dispersive (van der Waals) forces, so that a large and important class systems remains outside scope DFT. vdW-DF Langreth Lundqvist, published 2004, was first...
We analyse recently measured nonlinear photoemission spectra from Ag surfaces that reveal resonances whose energies do not scale with the applied photon energy but stay pinned to multiples of bulk plasmon $\hbar\omega_p$ above Fermi level. To elucidate these unexpected and peculiar features we investigate plasmons generated in a solid by optically pumped electronic polarization their effect on photoemission. By combining quadratic response formalism for calculations yield, nonperturbative...
The surface-phonon-dispersion curves of commensurate Xe monolayers on Cu(111) and incommensurate Cu(001) surfaces have been measured using He-atom scattering (HAS) time-of-flight (TOF) spectroscopy. TOF spectra are interpreted by combining quantum calculations with the dynamical matrix description surface vibrations. Both a vertically polarized Einstein-like mode another, acousticlike dominantly longitudinal character identified. latter is characterized presence absence zone-center frequency...