Related papers: Refraction and absorption of x rays by laser-dress…
We investigated the complex index of refraction in the x-ray regime of atoms in laser light. The laser (intensity up to 10^13 W/cm^2, wavelength 800nm) modifies the atomic states but, by assumption, does not excite or ionize the atoms in…
Electromagnetically induced transparency (EIT) is predicted for x rays in laser-dressed neon gas. The x-ray photoabsorption cross section and polarizability near the Ne K edge are calculated using an ab initio theory suitable for optical…
An ab initio theory is devised for the x-ray photoabsorption cross section of atoms in the field of a moderately intense optical laser (800nm, 10^13 W/cm^2). The laser dresses the core-excited atomic states, which introduces a dependence of…
This paper intends to realize negative refraction with absorption suppressed by the electromagneticly induced transparency(EIT) in a dense four-level atomic system. Without the two equal transition frequencies responding to the probe field,…
The nonlinear absorption of laser radiation of relativistic intensities in the underdense plasma by a mechanism of stimulated bremsstrahlung of electrons on the ions/nuclei is investigated in the low frequency approximation. Coefficient of…
We present a theoretical study of transient absorption and reshaping of extreme ultraviolet (XUV) pulses by helium atoms dressed with a moderately strong infrared (IR) laser field. We formulate the atomic response using both the…
The electronic excitation occurring on adsorbates at ultrafast time scales from optical lasers that initiate surface chemical reactions is still an open question. Here, we report the ultrafast temporal evolution of X-ray absorption…
Electron capture processes are important in the search for new physics. In this context, a high capture rate is desired. We investigate the possibility of enhancing the electron capture rate by irradiating laser beam to ''atom''. The…
A metamaterial perfect absorber consisting of a tri-layer (Al/ZnS/Al) metal-dielectric-metal system with top aluminium nano-disks is fabricated by laser-interference lithography and lift-off processing. The metamaterial absorber had peak…
On the base of the quantum kinetic equation for density matrix in plasma at the stimulated bremsstrahlung of electrons on ions, the nonlinear absorption rate for high-intensity shortwave radiation in plasma has been obtained within…
Exploration of a new ultrafast-ultrasmall frontier in atomic and molecular physics has begun. Not only is is possible to control outer-shell electron dynamics with intense ultrafast optical lasers, but now control of inner-shell processes…
When an electromagnetic wave is obliquely incident on an inhomogeneous high density plasma, it will be absorbed resonantly as long as it is polarized in the plane of incidence and has an electric field component along the plasma electron…
Well-known Kato's theory of the Laue diffraction of spherical x-ray waves is generalized to the case of the neutron diffraction in strongly absorbing crystals, taking into consideration both the potential and the resonant scattering of…
Absorption covers the physical processes which convert intense photon flux into energetic particles when a high-power laser illuminates optically-thick matter. It underpins important petawatt-scale applications today, e.g., medical-quality…
We devise a theory of x-ray absorption by symmetric-top molecules which are aligned by an intense optical laser. Initially, the density matrix of the system is composed of the electronic ground state of the molecules and a thermal ensemble…
In very intense electromagnetic fields, the vacuum refractive index is expected to be modified due to nonlinear quantum electrodynamics (QED) properties. Several experimental tests using high intensity lasers have been proposed to observe…
We present a non-Hermitian theory of atomic and molecular absorption, which enables computing the absorption spectrum of multi-electron atoms and molecules without using any fitting parameters. We propose a method for optically inducing…
Applications of negative index materials (NIM) presently are severely limited by absorption. Next to improvements of metamaterial designs, it has been suggested that dense gases of atoms could form a NIM with negligible losses. In such…
We investigate the non-linear response and energy absorption in bulk silicon irradiated by intense 12-fs near-infrared laser pulses. Depending on the laser intensity, we distinguish two regimes of non-linear absorption of the laser energy:…
Absorption imaging of ultracold atoms is the foundation for quantitative extraction of information from experiments with ultracold atoms. Due to the limited exposure time available in these systems, the signal-to-noise ratio is largest for…