相关论文: Interference between Extrinsic and Intrinsic Losse…

Probing optical excitations with high resolution is important for understanding their dynamics and controlling their interaction with other photonic elements. This can be done using state-of-the-art electron microscopes, which provide the…

Recent studies of QSOs with ROSAT suggest the existence of a significant population of Soft X-ray Weak QSOs (SXW QSOs) where the soft X-ray flux is ~ 10-30 times smaller than in typical QSOs. As a first step in a systematic study of these…

We develop a theoretical description of intravalley scattering of quasiparticles in graphene from multiple short-range scatterers of size much greater than the carbon-carbon bond length. Our theory provides a method to rapidly calculate the…

We describe a method for calculating the resonant inelastic X-ray scattering (RIXS) response---including the dynamics of the transient core hole---of many-body systems with non-trivial gap structure encoded in their single particle Green's…

Employing a recently developed technique of component weighted two particle Green's functions in the CPA of a binary substitutional alloy $A_cB_{1-c}$ we extend the existing theory of excitons in such media using a contact potential model…

We employ Non-equilibrium Green's functions (NEGF) to describe the real-time dynamics of an adsorbate-surface model system exposed to ultrafast laser pulses. For a finite number of electronic orbitals, the system is solved exactly and…

We present a calculation of the spectral properties of a single charge doped at a Cu($3d$) site of the Cu-F plane in KCuF$_{3}$. The problem is treated by generating the equations of motion for the Green's function by means of subsequent…

Enhancing the absorption and emission of electromagnetic waves over a broad range of wavelengths is a topic of fundamental and applied interest in photonics and energy research. In the context of light trapping in solar cells, for example,…

In polar semiconductors and insulators, the Fr\"ohlich interaction between electrons and long-wavelength longitudinal optical phonons induces a many-body renormalization of the carrier effective masses and the appearence of characteristic…

We theoretically analyze the intensity of the resonant inelastic X-ray scattering (RIXS) based on Ansatz that the electron is fractionalized into two components. By fitting the angle resolved photoemission spectroscopy (ARPES) data of a…

A many-body theory based on nonequilibrium Green functions, in which transport and optics are treated on a microscopic quantum mechanical basis, is used to compute gain and absorption in the optical and THz regimes in quantum cascade laser…

We analyze the resonant inelastic x-ray scattering (RIXS) spectra at the K edge of Mn in the antiferromagnetic insulating manganite LaMnO3. We make use of the Keldysh-type Green-function formalism, in which the RIXS intensity is described…

Resonant inelastic x-ray scattering (RIXS) has become a powerful tool in the study of the electronic structure of condensed matter. Although the linewidths of many RIXS features are narrow, the experimental broadening can often hamper the…

Resonant inelastic X-ray scattering (RIXS) is used increasingly for characterizing low-energy collective excitations in materials. RIXS is a powerful probe, which often requires sophisticated theoretical descriptions to interpret the data.…

We use analytical examples and asymptotic forms to examine the mathematical structure and physical meaning of the seismic cross correlation measurement. We show that in general, cross correlations are not Green's functions of medium, and…

First principles simulation of x-ray photoemission spectroscopy (XPS) is an important tool in the challenging interpretation and assignment of XPS data of metal-organic interfaces. We investigate the origin of the disagreement between XPS…

When x-rays penetrate soft matter, their phase changes more rapidly than their amplitude. In- terference effects visible with high brightness sources creates higher contrast, edge enhanced images. When the object is piecewise smooth (made…

Absorbing a focused, femtosecond X-ray pulse from a Free-Electron Laser (FEL) can lead to extreme electronic excitations in solids. This excitation drives changes of the electronic system over the course of the pulse duration and the…

We present a real-space Green's function theory and calculations of two-photon x-ray absorption (TPA). Our focus is on non-resonant K-shell TPA in metallic Cu, which has been observed experimentally at intense x-ray free electron laser…

This work provides an in-depth mathematical description of the response functions that are used for spatial and spectral analysis of X-ray data. The use of such functions is well-known to anyone familiar with the analysis of X-ray data…