Related papers: Full bandstructure calculation of second harmonic …
We consider 2D gas of spinless fermions with the Coulomb and the short range interactions on a square lattice at T=0. Using exact diagonalization technique we study finite clusters up to 16 particles at filling factors $\nu=1/2$ and 1/6. By…
As an extension of previous theoretical study on the coherent structure resonance due to space charge effects [Chao Li and R. A. Jameson, Phys. Rev. Accel. Beams 21, 024204, 2018], this paper aims to demonstrate how the beam, as a whole, is…
The structural and electronic properties of $A$TiO$_3$ ($A$=Ca, Sr, Ba) have been investigated under strain-free situation and with realistic constraints using first-principles calculations. We endeavored to find out the interplay between…
Second harmonic generation (SHG) is forbidden in centrosymmetric molecular materials. However, a signal is frequently observed from interfaces where the symmetry is broken. Whereas the effect can be phenomenologically accommodated, an ab…
Structural, magnetic and electrical-transport properties of {\alpha}-LiFeO2, crystallizing in the rock salt structure with random distribution of Li and Fe ions, have been studied by synchrotron X-ray diffraction, 57Fe M\"ossbauer…
Nonlinear optics of semiconductors is an important field of fundamental and applied research, but surprisingly the role of excitons in the coherent processes leading to harmonics generation has remained essentially unexplored. Here we…
The critical fluctuations in SrTiO$_3$ near its $105 K$ structural phase transition were studied with triple axis diffractometry using high energy ($\ge 100 keV$) synchrotron radiation in different SrTiO$_3$ crystals with different oxygen…
High-power infrared laser systems with broadband tunability are of great importance due to their wide range of applications in spectroscopy and free-space communications. These systems require nonlinear optical (NLO) crystals for wavelength…
Femtosecond pump-probe second-harmonic generation (SHG) and transient linear reflectivity measurements were carried out on polycrystalline Cu, Ag and Au in air to analyze whether the electron temperature affects Fresnel factors or nonlinear…
To investigate the pressure-induced structural transitions of chromium dioxide (CrO$_{2}$), phonon dispersions and total energy band structures are calculated as a function of pressure. The first structural transition has been confirmed at…
We study surface second-harmonic generation (SHG) from a singular plasmonic structure consisting of touching metallic wires. We use the technique of transformation optics and relate the structure to a rather simpler geometry, a slab…
We present in detail the formulation of the ab initio theory we have developed for the calculation of the macroscopic second-order susceptibility $\chi^{(2)}$. We find a general expression for $\chi^{(2)}$ valid for any fields, containing…
We combine modeling and experiments to investigate second- and third-harmonic generation (SHG/THG) in metal-indium tin oxide (ITO) metasurfaces. Linear optics at normal incidence show moderate field enhancement near the ITO…
The relationship between magnetic order and the second harmonic generation (SHG) effect is a fundamental area of study in condensed matter physics with significant practical implications. In order to gain a clearer understanding of this…
Various interference effects are known to exist in the process of high harmonic generation (HHG) both at the single atom and macroscopic levels. In particular, the quantum path difference between the long and short trajectories of electron…
Based on recent developments in the first-principles theory of flexoelectricity, we generalize the concept of absolute deformation potential to arbitrary nonpiezoelectric insulators and deformation fields. To demonstrate our formalism, we…
Optical measurements under externally applied stresses allow us to study the materials' electronic structure by comparing the pressure evolution of optical peaks obtained from experiments and theoretical calculations. We examine the…
The electronic band structure of SrTiO$_3$ is investigated in the all-electron QS$GW$ approximation. Unlike previous pseudopotential based QS$GW$ or single-shot $G_0W_0$ calculations, the gap is found to be significantly overestimated…
The microscopic mechanism of the hydrogen-induced metal-insulator transition in SmNiO$_3$ is clarified by means of density-functional theory with the Hubbard U correction. While 100% of hydrogen doping per Ni atom has been supposed to be…
We study the effective second-harmonic generation (SHG) susceptibility in graded metallic films by invoking the local field effects exactly, and further numerically demonstrate that the graded metallic films can serve as a novel optical…