A5070854974- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Quantum Chromodynamics and Particle Interactions
- Cold Atom Physics and Bose-Einstein Condensates
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Advanced Fiber Laser Technologies
- High-pressure geophysics and materials
- Mechanical and Optical Resonators
- Black Holes and Theoretical Physics
- Advanced X-ray Imaging Techniques
- Particle Accelerators and Free-Electron Lasers
- Laser Design and Applications
- Quantum Electrodynamics and Casimir Effect
- Atomic and Subatomic Physics Research
- Pulsars and Gravitational Waves Research
- Physics of Superconductivity and Magnetism
- Orbital Angular Momentum in Optics
- Photonic and Optical Devices
- Dark Matter and Cosmic Phenomena
- Atomic and Molecular Physics
- Quantum, superfluid, helium dynamics
- Nuclear Physics and Applications
- Random lasers and scattering media
- Quantum Mechanics and Applications
Friedrich Schiller University Jena
2016-2025
Helmholtz Institute Jena
2016-2025
GSI Helmholtz Centre for Heavy Ion Research
2021-2025
Friedrich-Alexander-Universität Erlangen-Nürnberg
2007-2010
Upcoming and planned experiments combining increasingly intense lasers energetic particle beams will access new regimes of nonlinear, relativistic, quantum effects. This improved experimental capability has driven substantial progress in QED background fields. We review here the advances made during last decade, with a focus on theory phenomenology. As ever higher intensities are reached, it becomes necessary to consider processes at orders both number scattered particles loops, account for...
We study the effective interactions of external electromagnetic fields induced by fluctuations virtual particles in vacuum quantum electrodynamics. Our main focus is on these at two-loop order. discuss detail emergence renowned Heisenberg-Euler action from underlying microscopic theory electrodynamics, emphasizing its distinction a standard one-particle irre-ducible action. In our explicit calculations we limit ourselves to constant and slowly varying fields, allowing us adopt locally field...
Birefringence is one of the fascinating properties vacuum quantum electrodynamics (QED) in strong electromagnetic fields. The scattering linearly polarized incident probe photons into a perpendicularly mode provides distinct signature optical activity and thus offers an excellent opportunity for precision test non-linear QED. Precision tests require accurate predictions theoretical framework that capable taking detailed experimental geometry account. We derive analytical solutions...
We study the effect of stimulated photon emission from vacuum in strong space-time-dependent electromagnetic fields. emphasize viewpoint that subjected to macroscopic fields with at least one nonzero field invariant, as, e.g., attainable by superimposing two laser beams, can represent a source term for outgoing photons. believe this view is particularly intuitive and allows straightforward optical signatures quantum nonlinearity realistic experiments involving collision high-intensity...
Abstract The Gamma Factory (GF) is an ambitious proposal, currently explored within the CERN Physics Beyond Colliders program, for a source of photons with energies up to ≈400 MeV and photon fluxes (up ≈10 17 s −1 ) exceeding those available gamma sources by orders magnitude. high‐energy (secondary) are produced via resonant scattering primary laser highly relativistic partially‐stripped ions circulating in accelerator. secondary emitted narrow cone energy beam can be monochromatized, down...
We aim at insights about how localization of the background field impacts nonlinear quantum vacuum signatures probed by photons in purely magnetic, electric and crossed fields. The starting point our study are one-loop results for Heisenberg-Euler effective Lagrangian photon polarization tensor electrodynamics (QED) evaluated a uniform constant electromagnetic field. As is well known often employed, especially weak-field limit, within certain restrictions these also allow reliable analysis...
Laser pulse collisions are a promising tool for the investigation of light-by-light scattering phenomena induced by quantum vacuum fluctuations. Using numerical code based on emission picture and put forward in [1], we observe strong dependence signal features transverse profiles colliding laser pulses interaction region. For probe beam tailored such as to feature an annular far-field profile pronounced on-axis focus peak counterpropagating pump at zero impact parameter, signal’s main...
Abstract Quantum field theory predicts a nonlinear response of the vacuum to strong electromagnetic fields macroscopic extent. This fundamental tenet has remained experimentally challenging and is yet be tested in laboratory. A particularly distinct signature resulting optical activity quantum birefringence. offers an excellent opportunity for precision test electrodynamics uncharted parameter regime. Recently, operation high-intensity Relativistic Laser at X-ray Free Electron provided by...
We revisit the photon polarization tensor in a homogeneous external magnetic or electric field. The starting point of our considerations is momentum space representation one-loop presence electromagnetic field, known terms double parameter integral. Our focus on explicit analytical insights for both on- and off-the-light-cone dynamics wide range well-specified physical regimes, ranging from perturbative to manifestly nonperturbative strong field regime. basic ideas underlying...
Vacuum birefringence is one of the most striking predictions strong field quantum electrodynamics: Probe photons traversing a region can indirectly sense applied ``pump'' electromagnetic via fluctuations virtual charged particles which couple to both pump and probe fields. This coupling sensitive alignment effectively result in two different indices refraction for photon polarization modes giving rise phenomenon. In this article, we perform dedicated theoretical analysis proposed discovery...
We study all-optical signatures of the effective nonlinear couplings among electromagnetic fields in quantum vacuum, using collision two focused high-intensity laser pulses as an example. The experimental vacuum nonlinearities are encoded signal photons, whose kinematic and polarization properties differ from photons constituting macroscopic fields. implement efficient numerical algorithm allowing for theoretical investigation such realistic field configurations accessible experiment. This...
The tremendous progress in high-intensity laser technology and the establishment of dedicated high-field laboratories recent years have paved way towards a first observation quantum vacuum nonlinearities at frontier. We advocate particularly prospective scenario, where three synchronized pulses are brought into collision, giving rise to signal photons, whose frequency propagation direction differ from driving pulses, thus providing various means achieve an excellent background separation....
We provide an explicit expression for the strong magnetic field limit of Heisenberg-Euler effective Lagrangian both scalar and spinor quantum electrodynamics. To this end, we show that behavior is fully determined by one-particle reducible contributions discovered only recently. The latter can efficiently be constructed in essentially algebraic procedure from lower-order diagrams. Remarkably, leading all-loop requires input one-loop Lagrangian. Our result revises previous findings based...
Quantum field theory predicts the vacuum to exhibit a non-linear response strong electromagnetic fields. This fundamental tenet has remained experimentally challenging and is yet be tested in laboratory. We present proof of concept detailed theoretical analysis an experimental setup for precision measurements quantum signal generated by collision brilliant x-ray probe with high-intensity pump laser. The features components polarised parallel perpendicularly incident probe. Our...
Starting from the Heisenberg-Euler effective Lagrangian, we determine photon current and polarization tensor in inhomogeneous, slowly varying electromagnetic fields. To this end, consider background field configurations both space time, paying special attention to structure. As a main result, obtain compact analytical expressions for realistic Gaussian laser pulses, as generated focal spots of high-intensity lasers. These are utmost importance investigation quantum vacuum nonlinearities experiments.
All-optical experiments at the high-intensity frontier offer a promising route to unprecedented precision tests of quantum electrodynamics in strong macroscopic electromagnetic fields. So far, most theoretical studies all-optical signatures vacuum nonlinearity are based on simplifying approximations beam profiles and pulse shapes driving laser Since require accurate quantitative predictions, we introduce an efficient numerical tool facilitating study generic Our approach is emission picture,...
We put forward a concrete experimental setup allowing to measure light-by-light scattering in the collision of two optical high-intensity laser beams at state-of-the-art high-field facilities operating petawatt class systems. Our uses same focusing optics for both be collided and employs dark-field approach detection single-photon-level nonlinear quantum vacuum response presence large background. Based on an advanced modeling colliding fields, we particular provide reliable estimates...
We study the effect of laser photon merging, or equivalently high harmonic generation, in quantum vacuum subject to inhomogeneous electromagnetic fields. Such a process is facilitated by effective nonlinear couplings arising from charged particle-antiparticle fluctuations strong derive explicit results for general kinematic and polarization configurations involving optical photons. Concentrating on merged photons reflected channels which are preferable experiments reasons noise suppression,...
The focus of this article is on providing compact analytical expressions for the differential number polarization flipped signal photons constituting vacuum birefringence in head-on collision x-ray free electron (XFEL) and optical high-intensity laser pulses. Our results allow unprecedented insights into scaling effect with waists pulse durations both beams, Rayleigh range beam, as well transverse longitudinal offsets. They account decay far-field a function azimuthal angle measured relative...
We show that coherent harmonic focusing provides an efficient mechanism to boost all-optical signatures of quantum vacuum nonlinearity in the collision high-intensity laser fields, thereby offering a promising route their first experimental detection. Assuming two pulses given parameters at our disposal, we demonstrate substantial increase number signal photons measurable experiments where one undergoes before it collides with fundamental-frequency pulse. Imposing quantitative criterion...
We study the perspectives of measuring phenomenon vacuum birefringence predicted by quantum electrodynamics using an x-ray free-electron laser (XFEL) alone. devise experimental scheme allowing XFEL beam to collide with itself under a finite angle, and thus act as both pump probe field for effect. The signature is encoded in polarization-flipped signal photons be detected high-purity polarimetry. Our findings idealized scenarios underline that discovery potential solely XFEL-based setups can...
Using the exactly solvable Gross-Neveu model as theoretical laboratory, we analyze in detail relationship between a relativistic quantum field theory at real and imaginary chemical potential. We find that one can retrieve full information about phase diagram of from an potential calculation. The prerequisite is to evaluate analytically continue effective for chiral order parameter, rather than thermodynamic observables or boundaries. In case inhomogeneous phase, needs compute action,...
We investigate photon merging and splitting processes in inhomogeneous, slowly varying electromagnetic fields. Our study is based on the three-photon polarization tensor following from Heisenberg-Euler effective action. put special emphasis deviations well-known constant field results, also revisiting selection rules for these processes. In context of high-intensity laser facilities, we analytically determine compact expressions number merged/split photons as obtained focal spots intense...