strong field
Recently Published Documents


TOTAL DOCUMENTS

2564
(FIVE YEARS 512)

H-INDEX

92
(FIVE YEARS 12)

Author(s):  
Leonard Doyle ◽  
Pooyan Khademi ◽  
Peter Hilz ◽  
Alexander Sävert ◽  
Georg Schaefer ◽  
...  

Abstract High power short pulse lasers provide a promising route to study the strong field effects of the quantum vacuum, for example by direct photon-photon scattering in the all-optical regime. Theoretical predictions based on realistic laser parameters achievable today or in the near future predict scattering of a few photons with colliding Petawatt laser pulses, requiring single photon sensitive detection schemes and very good spatio-temporal filtering and background suppression. In this article, we present experimental investigations of this photon background by employing only a single high power laser pulse tightly focused in residual gas of a vacuum chamber. The focal region was imaged onto a single-photon sensitive, time gated camera. As no detectable quantum vacuum signature was expected in our case, the setup allowed for characterization and first mitigation of background contributions. For the setup employed, scattering off surfaces of imperfect optics dominated below the residual gas pressures of 1×10-4mbar. Extrapolation of the findings to intensities relevant for photon-photon scattering studies is discussed.


Author(s):  
Boris N Latosh ◽  
Andrej B Arbuzov ◽  
Andrej Nikitenko

Abstract One-loop effective potential of scalar-tensor gravity with a quartic scalar field self-interaction is evaluated up to first post-Minkowskian order. The potential develops an instability in the strong field regime which is expected from an effective theory. Depending on model parameters the instability region can be exponentially far in a strong field region. Possible applications of the model for inflationary scenarios are highlighted. It is shown that the model can enter the slow-roll regime with a certain set of parameters.


Nanophotonics ◽  
2022 ◽  
Vol 0 (0) ◽  
Author(s):  
Kyosuke Sakai ◽  
Hiroki Kitajima ◽  
Keiji Sasaki

Abstract Plasmonic nanostructures have considerable applicability in light–matter interactions owing to their capacity for strong field confinement and enhancement. Nanogap structures allow us to tailor electric field distributions at the nanoscale, bridging the differences in size and shape of atomic and light structures. In this study, we demonstrated that a plasmonic tetramer structure can squeeze structured light into a nanoscale area, in which a strong field gradient allows access to forbidden transitions. Numerical simulations showed that the gold tetramer structure on a glass substrate possesses a plasmonic eigenmode, which forms structured light with a quadrupole profile in the nanogap region at the center of the tetramer. The top–down technique employed using electron-beam lithography allows us to produce a gap size of approximately 50 nm, which supports plasmonic resonance in the near-infrared regime. In addition, we demonstrated an array architecture in which a collective lattice resonance enhances the intensity of the quadrupole field in multiple lattice units. This study highlights the possibility of accessing multipolar transitions in a combined system of structured light and plasmonic nanostructures. Our findings may lead to new platforms for spectroscopy, sensing, and light sources that take advantage of the full electronic spectrum of an emitter.


2022 ◽  
Vol 11 (1) ◽  
Author(s):  
Moritz B. Heindl ◽  
Nicholas Kirkwood ◽  
Tobias Lauster ◽  
Julia A. Lang ◽  
Markus Retsch ◽  
...  

AbstractMicroscopic electric fields govern the majority of elementary excitations in condensed matter and drive electronics at frequencies approaching the Terahertz (THz) regime. However, only few imaging schemes are able to resolve sub-wavelength fields in the THz range, such as scanning-probe techniques, electro-optic sampling, and ultrafast electron microscopy. Still, intrinsic constraints on sample geometry, acquisition speed and field strength limit their applicability. Here, we harness the quantum-confined Stark-effect to encode ultrafast electric near-fields into colloidal quantum dot luminescence. Our approach, termed Quantum-probe Field Microscopy (QFIM), combines far-field imaging of visible photons with phase-resolved sampling of electric waveforms. By capturing ultrafast movies, we spatio-temporally resolve a Terahertz resonance inside a bowtie antenna and unveil the propagation of a Terahertz waveguide excitation deeply in the sub-wavelength regime. The demonstrated QFIM approach is compatible with strong-field excitation and sub-micrometer resolution—introducing a direct route towards ultrafast field imaging of complex nanodevices in-operando.


2022 ◽  
Vol 2022 (1) ◽  
Author(s):  
Abhay Ashtekar ◽  
Neev Khera ◽  
Maciej Kolanowski ◽  
Jerzy Lewandowski

Abstract It is well-known that blackhole and cosmological horizons in equilibrium situations are well-modeled by non expanding horizons (NEHs) [1–3]. In the first part of the paper we introduce multipole moments to characterize their geometry, removing the restriction to axisymmetric situations made in the existing literature [4]. We then show that the symmetry group $$ \mathfrak{G} $$ G of NEHs is a 1-dimensional extension of the BMS group $$ \mathfrak{B} $$ B . These symmetries are used in a companion paper [5] to define charges and fluxes on NEHs, as well as perturbed NEHs. They have physically attractive properties. Finally, it is generally not appreciated that $$ \mathcal{I} $$ I ±of asymptotically flat space-times are NEHs in the conformally completed space-time. Forthcoming papers will (i) show that $$ \mathcal{I} $$ I ± have a small additional structure that reduces $$ \mathfrak{G} $$ G to the BMS group $$ \mathfrak{B} $$ B , and the BMS charges and fluxes can be recovered from the NEH framework; and, (ii) develop gravitational wave tomography for the late stage of compact binary coalescences: reading-off the dynamics of perturbed NEHs in the strong field regime (via evolution of their multipoles), from the waveform at $$ \mathcal{I} $$ I +.


2022 ◽  
Vol 2022 (1) ◽  
Author(s):  
Felix Karbstein

Abstract We advocate the study of external-field quantum electrodynamics with N charged particle flavors. Our main focus is on the Heisenberg-Euler effective action for this theory in the large N limit which receives contributions from all loop orders. The contributions beyond one loop stem from one-particle reducible diagrams. We show that specifically in constant electromagnetic fields the latter are generated by the one-loop Heisenberg-Euler effective Lagrangian. Hence, in this case the large N Heisenberg-Euler effective action can be determined explicitly at any desired loop order. We demonstrate that further analytical insights are possible for electric-and magnetic-like field configurations characterized by the vanishing of one of the secular invariants of the electromagnetic field and work out the all-orders strong field limit of the theory.


Author(s):  
С.А. Богданов ◽  
А.А. Борисов ◽  
С.Н. Карпов ◽  
М.В. Кулиев ◽  
А.Б. Пашковский ◽  
...  

The nonlocal electrons heating in transistor heterostructures based on gallium nitride and arsenide is compared. It is shown that if, in comparison with a pure bulk material, in the case of GaAs double doped pseudomorphic heterostructures, the real space transfer of electrons significantly reduces their drift velocity overshot in the region of a strong field, then for GaN-based heterostructures, the decrease of the drift velocity overshot in the studied cases does not exceed 30%.


2021 ◽  
Vol 127 (27) ◽  
Author(s):  
D. Trabert ◽  
N. Anders ◽  
S. Brennecke ◽  
M. S. Schöffler ◽  
T. Jahnke ◽  
...  

Laser Physics ◽  
2021 ◽  
Vol 32 (2) ◽  
pp. 025001
Author(s):  
XingKang Li ◽  
Shuwen Mao ◽  
Penghang Yu ◽  
JianPing Chang ◽  
Youwei Tian

Abstract We have studied the high harmonic radiation property from the scattering of an electron with a focused few-cycle laser pulse by analyzing the distribution of the radiation field and the motion state of the electron. In the time domain, temporal width of the compressed radiation can reach 33 zs (zeptosecond), thus an ultrashort x-ray pulse was generated in the interaction process. The radiation in this process is vastly similar to high harmonic generation in the process of atomic strong-field. The latter depends to a large extent on the phase of carrier-envelope (CE) driving laser pulse. The cutoff of radiation spectrum can reach 1 × 10 5 ω 0 , and whether the high-order harmonic spectrum in the cut-off region can be well resolved depends on the CE phase. We have investigated the relationship between the maximum radiation intensity and the CE phase, and discussed a potential method to characterize the CE phase of an intense few-cycle laser pulse for broader application prospects.


Sign in / Sign up

Export Citation Format

Share Document