A5033537671- Laser-Matter Interactions and Applications
- Laser-Plasma Interactions and Diagnostics
- Advanced X-ray Imaging Techniques
- SAS software applications and methods
- Gamma-ray bursts and supernovae
- Advanced Fiber Laser Technologies
- Laser-induced spectroscopy and plasma
- High-pressure geophysics and materials
- Particle Accelerators and Free-Electron Lasers
- X-ray Spectroscopy and Fluorescence Analysis
- Photorefractive and Nonlinear Optics
- Laser Material Processing Techniques
- Theoretical and Computational Physics
- Advanced Electron Microscopy Techniques and Applications
- Atomic and Molecular Physics
- Semiconductor Lasers and Optical Devices
- Crystallography and Radiation Phenomena
- Quantum many-body systems
- Optical Network Technologies
- Laser Design and Applications
- Superconducting Materials and Applications
- GaN-based semiconductor devices and materials
- Particle physics theoretical and experimental studies
- Physics of Superconductivity and Magnetism
- Ga2O3 and related materials
University of Lisbon
2015-2024
Instituto Superior Técnico
2013-2023
Instituto Politécnico de Lisboa
2013-2022
Université de Limoges
2021
XLIM
2021
Centre National de la Recherche Scientifique
2021
Lebanese American University
2021
Lahore University of Management Sciences
2021
Instituto Superior de Gestão
2021
Johnson Matthey (Germany)
2019
The efficiency and uniformity of heating induced by hard x-ray free-electron laser pulse is investigated for 0.5 μm silver foils using the X-ray Pump Probe instrument at Linac Coherent Light Source facility. Intense 8.9 keV pulses 60 fs duration deposit energy predominantly via inner-shell ionization to create a non-equilibrium Ag solid density plasma. are focused 14 × 17 μm2 means beryllium lenses varying total beam energy, deposition varied over range irradiances from 4.4 6.5 1015 W/cm2....
Incoherent Diffraction Imaging - IDI is a diffraction-based imaging technique that has been recently proposed to exploit the partial coherence of incoherently scattered light retrieve structural information from scattering centers. Similar stellar intensity interferometry Hanbury Brown and Twiss, signal builds up on second-order spatial correlations emitted light. The complex distribution target thereby encoded in fluctuations first experimental realisations this have realised using...
In atoms undergoing ionisation, an abrupt re-arrangement of free and bound electrons can lead to the ejection another electron (shake-off). The spectroscopic signatures shake-off have been predicted observed in solids. Here, we present first observation this process a solid-density plasma heated by x-ray laser. results show that L-shell persists up temperatures 10 eV at solid density, follow probability for This work shows should be included models correct interpretation emission spectra.
Non-thermal photo-ionized plasmas are now established in the laboratory, and require models that treat atomic processes electron distribution self-consistently. We investigate effects of inelastic thermalization iron under intense X-ray irradiation using model BigBarT, suited for self-consistent evolution continuum, including degeneracy effects. Our study focuses particularly on collisional $M$-shell ionization, which we identify as dominant relaxation process non-thermal electrons. show...
The phase diagrams of general $q$-state planar spin models on a square lattice are studied for $q=4\ensuremath{-}7$. calculated by variational method and the infinitesimal Migdal renormalization-group (RG) transformations. Since RG commutes with self-dual transformations $Z(q)$ models, one expects reliable (but not accurate critical exponents). In fact all exactly known points reproduced our calculations together fair numerical simulation lines points. Our results clearly indicate existence...
SUMMARY The relationship between the length of molar row and lower jaw in mammals is expressed by allometry equation y=bx k . A single formula cannot be applied to all Eutheria because value k, constant differential growth ratio, varies from group group. Variation would appear adaptive, for it increases a less than unity carnivores, through insectivores omnivores, exceeds herbivores. b decreases as increases, with result that most mammalian skulls have same when lies 90 110 mm. When full...
We demonstrate a method of using Fourier holographic technique to utilize attosecond soft x-ray pulses image nanometer-scale objects. A discrete frequency comb laser-generated high-order harmonics, yielding train pulses, has been used record spatially and spectrally resolved images. The individual wavelengths were also combined form single image, albeit with lower spatial resolution, demonstrating the applicability isolated continuous bandwidths.
We present measurements of photon absorption by free electrons as a solid is transformed to plasma. A femtosecond x-ray free-electron laser used heat solid, which separates the electron and ion heating time scales. The changes in are measured with an independent probe pulse created through high-order-harmonic generation. find increase temperature have relatively small impact on absorption, contrary several predictions, whereas increases absorption. compare data current theoretical numerical...
The collisional (or free-free) absorption of soft x rays in warm dense aluminium remains an unsolved problem. Competing descriptions the process exist, two which we compare to our experimental data here. One these is based on a weak scattering model, another uses corrected classical approach. These models show distinctly different behaviors with temperature. Here describe evidence for 26-eV photons solid density (${T}_{e}\ensuremath{\approx}1$ eV). Radiative x-ray heating from...
This paper describes new p-i-n-FET lightwave receivers that achieve high sensitivity without signal integration, and dynamic ranges large enough they cannot be saturated by present transmitters. IC versions can realized inexpensively in standard fine-line NMOS, CMOS, or GaAs technologies, thus are suitable for loop-plant, local-area-network, data link applications, as well long-haul transmission applications. These also readily designed bit-rates excess of 1 Gbit/s high-capacity systems. In...
The surge of interest in nonperturbative high-harmonic generation solids has been driven by the appeal compact solid-state extreme ultraviolet sources and prospect untangling material properties through response to strong fields. traditional assumption is that brighter, lower-order harmonics are purely perturbative nature. However, border between regimes often remains unclear. Here, we show third-harmonic (THG) using 800-nm, 40-fs pulses displays a wide-band-gap insulator MgO. Furthermore,...
A SINGLE-CHIP PREAMPLIFIER, which used lμ, NMOS technology, that has been designed for optical fiber PIN receivers, will be reported. The device, many applications, could replace hybrid IC (HIC) preamplifiers.
Thin films of nickel have been irradiated using femtosecond laser pulses in vacuum. Subsequent emission plasma ions is diagnosed an ion probe. Angular distributions the emitted are presented for a range target film thicknesses. Data compared to Anisimov model expansion [S. I. Anisimov, D. Bauerle, and B. S. Luk’yanchuk, Phys. Rev. B 48, 12076 (1993)]. The tendency be ejected at small angles normal surface explained terms initial conditions plume. Results shape adiabatic index plasma.
We report on the shot-to-shot stability of intensity and spatial phase high-harmonic generation (HHG). The is measured for each (HH) order with a spectrometer. Additionally, an XUV wavefront sensor single HH in shot, which according to our knowledge was not reported before Hartmann sensor. Furthermore, we compare single-shot measurement time-integrated measurements show that useful tool simultaneously optimize HHG within available parameter range used this study.
SUMMARY. The abdomen of the female Pea‐Crab Pinnotheres yisum shows an extremely high growth‐rate relative to that carapace, especially in early stages measured. That male very slight positive allometry. There is a shallow growth‐gradient with its centre segments V, VI. In gradient at first steep further back, between segment VI and telson. growth each three successive periods simple allometry progressively lower growth‐rate. second period fall less marked telson than immediately front....
With the advent of new x-ray light-sources worldwide, creation dense, uniformly heated plasma states arising from intense irradiation solids has been made possible. In early stages solid heating, before significant hydrodynamic motion occurs, matter exists in a highly non-equilibrium state. A method based on wavefront sensing is proposed to probe some fundamental properties these states. The deflection and absorption high harmonic beam propagated through can be measured with sensor, allow...
With high-harmonic generation (HHG), spatially and temporally coherent XUV to soft x-ray (100 nm 10 nm) table-top sources can be realized by focusing a driving infrared (IR) laser on gas target. For applications such as diffraction imaging, holography, plasma diagnostics, or pump-probe experiments, it is desirable have control over the wave front (WF) of HHs maximize number photons target tailor WF. Here, we demonstrate WF tailoring IR with deformable mirror. The WFs both beams are monitored...
One of the most successful ways to model multitude electron and photon processes in plasmas is approach used collisional radiative (CR) codes. The accuracy CR codes depends largely on rates each process. These are generally well approximated hot, classical plasmas. However, degenerate quantum effects can influence these must be accounted for. Previous approaches have developed corrections using free-electron-gas (FEG) approximation. Here, we use electronic structures beyond FEG approximation...