Related papers: Magic high-order harmonics from a quasi-one-dimens…
High-harmonic generation (HHG) provides the only source of attosecond pulses -- currently the shortest accessible time intervals, and it is employed as the only table-top source of light in extreme UV and soft X-ray spectral regions. Chiral…
We present theoretical predictions of high-order harmonic generation (HHG) resulting from the interaction of short femtosecond laser pulses with metal nanotips. It has been demonstrated that high energy electrons can be generated using…
High-harmonic generation (HHG) is a highly nonlinear optical process that typically requires an intense laser to trigger emissions at integer multiples of the driving field frequency. However, the strong fields required for conventional HHG…
Optical second-harmonic generation (SHG) is a nonlinear parametric process that doubles the frequency of incoming light. Only allowed in non-centrosymmetric materials, it has been widely used in frequency modulation of lasers, surface…
We show that high-order harmonics generated from molecules by intense laser pulses can be expressed as the product of a returning electron wave packet and the photo-recombination cross section (PRCS) where the electron wave packet can be…
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…
Generation of even-order optical harmonics requires noncentrosymmetric structures being conventionally observed in crystals lacking the center of inversion. In centrosymmetric systems, even-order harmonics may arise, e.g., at surfaces but…
High-order harmonic generation (HHG) from molecular ion HeH$^{2+}$ in two initial states of $1s\sigma$ (ground state) and $2p\sigma$ (first excited state) is investigated theoretically, in homogeneous and plasmonic-enhanced laser fields.…
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…
To clarify the microscopic origin of chirality-induced optical effect, we develop an analytical method that extracts the chiral part of the Hamiltonian of molecular electronic states. We demonstrate this method in a model chiral molecule…
Symmetries essentially provide conservation rules in nonlinear light-matter interactions, that facilitate control and understanding of photon conversion processes or electron dynamics. Since anisotropic solids have rich symmetries, they are…
A three step model for high harmonic generation from impurities in solids is developed. The process is found to be similar to high harmonic generation in atomic and molecular gases with the main difference coming from the non-parabolic…
We investigate the orientation dependence of high-order harmonic generation (HHG) from H$_2^+$ with different internuclear distances irradiated by intense laser fields both numerically and analytically. The calculated molecular HHG spectra…
High-order harmonic generation (HHG) is investigated for H$_2^+$ and its isotopomers under seven- and ten-cycle trapezoidal laser pulses at 800 nm wavelength and $I$=4$\times 10^{14}$ W$/$cm$^2$ intensity. We solved numerically…
A theoretical model is developed describing high-order harmonic generation (HHG) from a gas of multiply-charged ions driven by a laser field of relativistic intensity. Macroscopic propagation of harmonics is investigated in a relativistic…
Solids in an intense laser field show high-harmonic generation (HHG), which can provide information on carrier dynamics and band structures in weakly correlated systems. In strongly correlated systems, a laser field can induce a transition…
Strong-field methods in solids enable new strategies for ultrafast nonlinear spectroscopy and provide all-optical insights into the electronic properties of condensed matter in reciprocal and real space. Additionally, solid-state media…
High-harmonic generation is a light up-conversion process occurring in a strong laser field, leading to coherent bursts of extreme ultrashort broadband radiation [1]. As a new perspective, we propose that ultrafast strong-field electronic…
High-harmonic spectroscopy driven by circularly-polarized laser pulses and their counter-rotating second harmonic is a new branch of attosecond science which currently lacks quantitative interpretations. We extend this technique to the…
High-harmonic generation (HHG) in two-dimensional materials offers a compelling route toward compact extreme ultraviolet sources and probing electron dynamics on the attosecond scale. However, achieving precise control over the emission and…