A5070742264- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Atomic and Molecular Physics
- High-pressure geophysics and materials
- Advanced X-ray Imaging Techniques
- Laser-induced spectroscopy and plasma
- Laser Design and Applications
- Particle Accelerators and Free-Electron Lasers
- Gamma-ray bursts and supernovae
- Advanced Fiber Laser Technologies
- Cold Atom Physics and Bose-Einstein Condensates
- Magnetic confinement fusion research
- Advanced Fluorescence Microscopy Techniques
- Quantum Information and Cryptography
- Dark Matter and Cosmic Phenomena
- Advanced Optical Sensing Technologies
- Nuclear Physics and Applications
- Optical Coherence Tomography Applications
- Mass Spectrometry Techniques and Applications
- Random lasers and scattering media
- Quantum optics and atomic interactions
- Ion-surface interactions and analysis
- High-Energy Particle Collisions Research
- Stellar, planetary, and galactic studies
- Plasma Diagnostics and Applications
Ocean University of China
2021-2025
University of Plymouth
2019-2021
University of Gothenburg
2021
Max Planck Institute for Nuclear Physics
2017-2018
Beijing Normal University
2013-2017
Beijing Radiation Center
2017
China University of Mining and Technology
2017
University of British Columbia
2008
Abstract This Conceptual Design Report describes LUXE (Laser Und XFEL Experiment), an experimental campaign that aims to combine the high-quality and high-energy electron beam of European with a powerful laser explore uncharted terrain quantum electrodynamics characterised by both high energy intensity. We will reach this hitherto inaccessible regime physics analysing electron-photon photon-photon interactions in extreme environment provided intense focus. The background its relevance are...
Electron–positron pair production due to the decay of vacuum in ultrastrong laser fields is an interesting topic which revived recently because rapid development current technology. The theoretical and numerical research progress this challenging reviewed. Many new findings are presented by different approaches such as worldline instantons, S-matrix theory, kinetic method solving quantum Vlasov equation or/and real-time Dirac–Heisenberg–Wigner formalism, computational field theory Dirac so...
Accurate modeling is necessary to support precision experiments investigating strong-field QED phenomena. This particularly challenging in the transition between perturbative and nonperturbative regimes, where normalized laser amplitude a0 comparable unity wavelength-scale interference significant. Here, we describe how simulate nonlinear Compton scattering, Breit–Wheeler pair creation, trident creation this regime, using Monte Carlo particle-tracking code Ptarmigan. simulates collisions...
A factor that limits the use of multiphoton microscopy (MPM) in clinical and preclinical studies is lack a compact flexible probe. We report on miniaturized MPM probe employing microelectromechanical system (MEMS) scanning mirror double-clad photonic crystal fiber (DCPCF). The MEMS DCPCF provides many advantages, such as size reduction, rapid precise scanning, efficient delivery short pulses, high collection efficiency fluorescent signals. completed was 1 cm outer diameter 14 length....
We investigate the phenomenology of nonlinear Compton scattering polarised photons by unpolarised electrons in plane-wave backgrounds. The energy and angular spectra are calculated for linearly- circularly-polarised pulses, monochromatic fields constant crossed field When intensity is weakly regime, different polarisation states predicted to possess very distributions. explain this difference calculating spectrum Thomson a linearly-polarised background projecting electron's trajectory onto...
Fully polarized nonlinear Breit-Wheeler pair production from a beam of seed photons is investigated in pulsed plane wave backgrounds. The particle (electron and positron) spin photon polarization are comprehensively described with the theory density matrix. compact expressions for energy spectrum produced particles, depending on initial beam, derived discussed both linearly circularly laser numerical results suggest an appreciable improvement positron yield by orthogonalizing to...
We have formulated a generalized two level model for studying the vacuum electron-positron pair production in strong classical background fields via slowly varying envelope approximation. It can provide momentum spectra with fully spin resolved components all possible combined states of particle and antiparticle simultaneously multidimensional time-dependent electric fields. Moreover, we also investigated validity fermions (scalar particles) by comparing results those equal-time...
We detail a method to produce GeV-photon source with polarisation purity exceeding $96\%$ and $89\%$ for linear circular respectively brilliance of the order $10^{21}\,\textrm{photons}/(\textrm{s}~\textrm{mm}^2~\textrm{mrad}^2~0.1\%~\textrm{BW})$. Using currently available multi-GeV electron bunches laser pulses moderately relativistic intensities, we show how weakly nonlinear regime can photons polarised mainly parallel field. demonstrate robustness this scheme by considering various...
Radiative and nonradiative electron spin-flip probabilities are analyzed in both plane wave focused laser backgrounds. We provide a simple physically transparent description of spin dynamics waves, demonstrate that there exists kinematic regime which the usual leading-order perturbative hierarchy quantum electrodynamics is reversed, loop effects dominate over radiative tree-level flips. show while this dominance becomes suppressed pulses due to high sensitivity field geometry, nevertheless...
Spin effect on the pair production under circularly polarized fields is investigated. Significantly different from what momentum spirals caused by two counterrotating with a time delay, we find for first that can also be induced due to particle spin even if in single field. We further examine bichromatic combinational fields. The inhomogeneous spiral structures observed spectrum; particular, not only does exist cases of spin, but about 2 orders magnitude amplified compared Meanwhile,...
The momentum spectrum of multiphoton-created electrons in the presence a static potential well as an alternating field is found to be related electron energy levels and photons. A simple relation among three energies, created associated with distribution, level bound state, photon energy, obtained. Pair production can significantly enhanced by this two-field configuration. In case, depth frequency also need not supercritical.
The QED cascade induced by the two counterpropagating lasers is studied. It demonstrated that probability of a seed photon to create pair much larger than electron. By analyzing dynamic characteristics electron and positron created photon, it found particles are more likely emit photons With these results, furthermore, we demonstrate can be easily triggered with same incident energy laser.
The effect of the pulse envelope on electron-positron pair creation in a circularly polarized laser is investigated. Interference length scale envelope, and smoothness edges are found to influence spectrum. A toy model flat-top used identify effects inaccessible local approaches. Broadening channel openings widening energy transverse momentum distribution receive contributions that below harmonic threshold. By comparing yields flat-top, sine-squared Gaussian pulse, link between shape...
In many-cycle plane waves at intermediate intensities, the nonlinear trident process can be well approximated by two sequential steps of Compton scattering a polarized real photon followed its transformation into an electron-positron pair via Breit-Wheeler creation. We investigate this two-step in intensity regime employing locally monochromatic approximation for each step and numerically evaluating resulting expressions. When polarization is included, it found to produce order 10% decrease...
The creation of polarized electron-positron pairs by the nonlinear Breit-Wheeler process in short laser pulses is investigated using Baier-Katkov semiclassical method beyond local-constant-field approximation (LCFA), which allows for identifying interferences effects positron polarization. When intensity intermediate regime, pair production different formation lengths induce an enhancement probability spin-down positrons, significantly affects polarization created positrons. features are...
The photon spectrum from electrons scattering on multiple laser pulses exhibits interference effects not present for a single pulse. We investigate the conditions required experimental observation of these in electron-laser collisions, particular analysing roles detector resolution and transverse divergence pump electron beam.
We study the $2\ensuremath{\rightarrow}1$ process of electron-positron pair annihilation to a single photon in plane-wave background. The probability pulsed plane wave is presented, and locally constant field approximation derived benchmarked against exact results. stricter kinematics (compared $1\ensuremath{\rightarrow}2$ processes usually studied) leads stronger dependence on incoming particle states. demonstrate this by studying effect that initial-state packets have probability....
Abstract We propose a new laser-plasma-based method to generate bright γ -rays carrying large orbital angular momentum by interacting circularly polarized Laguerre–Gaussian laser pulse with near-critical hydrogen plasma confined in an over-dense solid tube. In the first stage of interaction, it is found via fully relativistic three-dimensional particle-in-cell simulations that high-energy helical electron beams are generated. second stage, this beam interacts reflected from disc behind tube,...
We investigate the optimization of photon polarization to increase yield Breit-Wheeler pair production in arbitrarily polarized plane wave backgrounds. show that optimized can improve positron by more than 20% compared unpolarized case, intensity regime current laser-particle experiments. The seed photon's optimal is result coupling with laser pulse. compact expressions coefficients both perturbative and nonperturbative regimes are given. Because evident difference for linear-...
Fully polarized Compton scattering from a beam of spin-polarized electrons is investigated in plane-wave backgrounds broad intensity region the perturbative to nonperturbative regimes. In regime, linear considered for investigating polarization transfer single laser photon scattered photon, and high-intensity region, locally monochromatic approximation constant field are established employed study an incoming electron photon. The numerical results suggest appreciable improvement about 10%...
In the quasistatic regimes of nonlinear Breit-Wheeler and trident pair creation, rates can exhibit a nonanalytic dependency on fundamental coupling quantum electrodynamics, in form similar to Schwinger vacuum creation. To reach this tunneling regime requires satisfying competing requirements: high-intensity but low strong-field parameter with sufficient creation be observed. Using locally monochromatic approach, we identify where could measured experiment. Studying several scenarios...
Plasma high harmonics generation from an extremely intense short-pulse laser is explored by including the effects of ion motion, electron-ion collisions and radiation reaction force in plasma dynamics. The pressure induces motion through hole-boring effect resulting into frequency shifting widening harmonic spectra. Classical slightly mitigates broadening caused motion. Based on results physical considerations, parameter maps highlighting optimum regions for generating a single attosecond...
High-energy photons can decay to electron-positron pairs via the nonlinear Breit-Wheeler process when colliding with an intense laser pulse. The energy spectrum of produced particles is broadened because variation their effective mass in course Applying a suitable chirp pulse narrow distribution generated electrons and positrons. We present scenario where high-energy electron beam collided chirped generate quasimonoenergetic $\ensuremath{\gamma}$ photons, which then second chirped, UV produce source
We develop an analytical model for ultraintense attosecond pulse emission in the highly relativistic laser-plasma interaction. In this model, is emitted by a strongly compressed electron layer around instant when transverse current changes sign and its longitudinal velocity approaches maximum. The has broadband exponential spectrum stabilized constant spectral phase $\psi(\omega)=\pm\pi/2-\psi_{A_m}$. waveform of also given explicitly, to our knowledge, first time. validate via...