Related papers: Nonlinearity in the sequential absorption of multi…
The invention of laser immediately enabled us to detect nonlinearities of photon interaction in matter, as manifested for example by Franken et al.'s detection of second harmonic generation and the excitation of the Brillouin forward…
We study the equivalence of four different approaches to calculate the excitonic linear and nonlinear optical response of multiband semiconductors. These four methods derive from two choices of gauge, i.e. length and velocity gauges, and…
The systems of nonlinear Volterra integral equations of the first kind with jump discontinuous kernels are studied. The iterative numerical method for such nonlinear systems is proposed. Proposed method employs the modified…
The correlated behavior of electrons determines the structure and optical properties of molecules, semiconductor and other systems. Valuable information on these correlations is provided by measuring the response to femtosecond laser…
When a weak decay competes with a strong decay in a 3-level atom, some mechanism is necessary to occasionally stop the strong decay so the weak decay can be completed. Rule (4) provides that mechanism. Using this rule, a weak photon is…
The idea of making photons effectively interact has attracted a lot of interest in recent years, for several reasons. Firstly, since photons do not naturally interact with each other, it is of fundamental physical interest to see what kind…
We study two-photon scattering of a tightly focused weak light beam from a small atomic ensemble of two-level atoms (2LAs). This is similar to the scattering of photons from an atomic ensemble in a one-dimensional waveguide. The scaling of…
X-ray free electron laser (XFEL) can provide X-ray light with about four order of magnitude higher flux than synchrotron radiation. Pulse light from XFEL interacts with the target and the resulting photons are collected by detectors. The…
In this work we provide a first principles description of the electronic and optical properties of bilayers C$_3$N, with different stacking motifs AB, AB$'$ and AA$'$. Starting from quasi-particle electronic band-structures, we solve the…
We show that it is not possible to discriminate two close transparencies without a certain number of photons being absorbed. We extend this to the discrimination of patterns of transparency (images).
We study coherent backscattering of a quasi-monochromatic laser by a dilute gas of cold two-level atoms. We consider the perturbative regime of weak intensities, where nonlinear effects arise from {\em inelastic} two-photon scattering…
The complementarity between time and energy, as well as between an angle and a component of angular momentum, is described at three different layers of understanding. The phenomena of super-resolution are readily apparent in the quantum…
We study photoabsorption reaction and real Compton scattering (RCS) within the color dipole model. We rely on a photon wave function derived in the instanton vacuum model, and on the energy dependent phenomenological elastic dipole…
We have carried out theoretical research on ultra-high resolution spectroscopy of atoms (or molecules) in the suggested cell with a series of plane-parallel thin gas layers between spatially separated gas regions of this cell for optical…
To shorten the duration of x-ray pulses, we present a nonlinear optical technique using atoms with core-hole vacancies (core-hole atoms) generated by inner-shell photoionization. The weak Coulomb screening in the core-hole atoms results in…
The coherent nonlinear process where a single photon simultaneously excites two or more two-level systems (qubits) in a single-mode resonator has recently been theoretically predicted. Here we explore the case where the two qubits are…
The Compton scattering of X-ray photons, assisted by a short intense optical laser pulse, is discussed. The differential scattering cross section reveals the interesting feature that the main Klein-Nishina line is accompanied by a series of…
Multiphoton femtosecond coherent control of is used for implementing innovative photo-induced analog coherent computation that generally might be a basis for future "smart hardware". The specific implemented computational task the…
The pulse intensity from X-ray free-electron lasers (FELs) can create extreme excitation densities in solids, entering the regime of non-linear X-ray-matter interactions. We show L3-edge absorption spectra of metallic nickel thin films with…
We investigate the nonlinear Compton photon source for upcoming laser-particle experiments in the collision scenario of high-energy electron beams and relativistic laser pulses. The stronger laser field could not only improve the scattering…