Related papers: High-harmonic generation from arbitrarily oriented…
High-order harmonic generation by a bicircular field, which consists of two coplanar counter-rotating circularly polarized fields of frequency $r\omega$ and $s\omega$ ($r$ and $s$ are integers), is investigated for a polyatomic molecule.…
We investigate the effect on high-order harmonic generation of the distortion of molecular orbitals by the driving laser field. Calculations for high-order harmonic generation including orbital distortion are performed for N2. Our results…
We report measurements and theoretical simulations of high-order harmonic generation (HHG) in aligned N$_2$ molecules using a 1200-nm intense laser field when the generating pulse is perpendicular to the aligning one. With increasing laser…
High-order harmonic generation (HHG) from aligned acetylene molecules interacting with mid infra-red (IR), linearly polarized laser pulses is studied theoretically using a mixed quantum-classical approach in which the electrons are…
We investigate high-harmonic generation in closed systems, using the two-level atom as a simplified model. By means of a windowed Fourier transform of the time-dependent dipole acceleration, we extract the main contributions to this process…
We perform a detailed analysis of high-order harmonic generation in diatomic molecules within the strong-field approximation, with emphasis on quantum-interference effects. Specifically, we investigate how the different types of electron…
High-order harmonic generation is a powerful and sensitive tool for probing atomic and molecular structures, combining in the same measurement an unprecedented attosecond temporal resolution with a high spatial resolution, of the order of…
We investigate the effect of dynamic electron correlation on high-harmonic generation in helium atoms using intense visible light (\lambda=390nm). Two complementary approaches are used which account for correlation in an approximate manner:…
The selection rules of high harmonic generation (HHG) are investigated using three-dimensional time-dependent density functional theory (TDDFT). From the harmonic spectra obtained with various real molecules and different forms of laser…
The relation between high-harmonic spectra and the geometry of the molecular orbitals in position and momentum space is investigated. In particular we choose two isoelectronic pairs of homonuclear and heteronuclear molecules, such that the…
We report a detailed study of high-order harmonic generation (HHG) in helium. When comparing predictions from a single-active-electron model with those from all-electron simulations, such as ATTOMESA and R-matrix with time-dependence, which…
We present theoretical investigations of high-order harmonic generation (HHG) resulting from the interaction of noble gases with localized surface plasmons. These plasmonic fields are produced when a metal nanoparticle is subject to a…
The generation of harmonics by atoms interacting with two circularly polarized and frequency related laser fields is addressed through ab initio numerical simulations. A detailed charaterization of a few specific harmonics is given. In…
We present results of relativistic calculations of even order harmonic generation from various atomic targets. The even order harmonics appear due to the relativistic non-dipole effects. We take these relativistic effects into account by…
We investigate the influence of intense, elliptically polarized driving fields on high-order harmonic spectra from aligned diatomic molecules. We derive a generalized two-center interference condition for elliptically polarized fields,…
We report the first experimental observation of frequency shift in high order harmonic generation (HHG) from isotopic molecules H2 and D2 . It is found that harmonics generated from the isotopic molecules exhibit obvious spectral red shift…
We observe the generation of high harmonics in the plane perpendicular to the driving laser polarization and show that these are driven by the spin-orbit interaction. Using R-Matrix with time-dependence theory, we demonstrate that for…
The generation of high-order harmonics in diatomic molecules is investigated within the framework of the strong-field approximation. We show that the conventional saddle-point approximation is not suitable for large internuclear distances.…
Recent measurements on high-order harmonic generation (HHG) from N$_2$ aligned perpendicular to the driving laser polarization [B. K. McFarland {\it el al}, Science {\bf 322}, 1232 (2008)] have shown a maximum at the rotational…
We theoretically investigate the interference effect of high-order harmonics generated from molecules at different alignment angles. It is shown that the interference of the harmonic emissions from molecules aligned at different angles can…