Related papers: High-order harmonic generation using a high-repeti…
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 generation (HHG) opens a window on the fundamental science of strong-field light-mater interaction and serves as a key building block for attosecond optics and metrology. Resonantly enhanced HHG from hot spots in…
High-order frequency mixing in graphene using a two-color radiation field consisting of the fundamental and the second harmonic fields of an ultrashort linearly polarized laser pulse is studied. It is shown that the harmonics originated…
Characterizing and controlling electronic properties of quantum materials require direct measurements of non-equilibrium electronic band structures over large regions of momentum space. Here, we demonstrate an experimental apparatus for…
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…
Attosecond light sources based on high-order harmonic generation (HHG) constitute to date the only table-top solution for producing coherent broadband radiation covering the spectral range from the extreme ultraviolet to the soft X-rays.…
Harmonic generation in the limit of ultra-steep density gradients is studied experimentally. Observations demonstrate that while the efficient generation of high order harmonics from relativistic surfaces requires steep plasma density…
Applying time-dependent local density approximation (TDLDA), we study the high-order harmonic generation (HHG) of ethylene subjected to the one-color ($\omega=2.72$ eV) and the two-color ($\omega_1=2.72$ eV and $\omega_2=5.44$ eV)…
We present theoretical studies of high-order harmonic generation (HHG) in rare gases driven by plasmonic field enhancement. This kind of fields appears when plasmonic nanostructures are illuminated by an intense few-cycle laser and have a…
High harmonic generation (HHG) has unleashed the power of strong laser physics in solids. Here we investigate HHG from a large system, solid C$_{60}$, with 240 valence electrons engaging harmonic generation at each crystal momentum, the…
Light generation through optical harmonics plays a pivotal role in photonics, driving innovations in coherent light sources, biological imaging, and spectroscopy. Traditional methods for tuning optical harmonics, including electrostatic…
We theoretically investigate photo-excitation of electron-hole pairs and high harmonic generation in the bulk of zinc oxide (ZnO) subjected to intense femto-second laser pulses with mid-infrared wavelength. The main microscopic mechanism of…
We present an experimental technique using orbital angular momentum (OAM) in a fundamental laser field to drive High Harmonic Generation (HHG). The mixing of beams with different OAM allows to generate two laser foci tightly spaced to study…
We demonstrate that phase-matched frequency upconversion of ultrafast laser light can be extended to shorter wavelengths by using longer driving laser wavelengths. Experimentally, we show that the phase-matching cutoff for harmonic…
High harmonic generation is a convenient way to obtain extreme ultraviolet light from table-top laser systems and the experimental tools to exploit this simple and powerful light source for time-resolved spectroscopy are being developed by…
In strong field laser physics it is a common practice to use the high-order harmonic cutoff to estimate the laser intensity of the pulse that generates the harmonic radiation. Based on the semiclassical arguments it is possible to find a…
We compare the enhancement of high-order harmonic generation in argon using 800--400 and 800--266~nm laser fields with their optimized single-color counterparts. We observe that the two-color fields generally outperform the single-color…
Anomalously high generation efficiency of coherent higher field-harmonics in collisions between {\em oppositely charged particles} in the field of femtosecond lasers is predicted. This is based on rigorous numerical solutions of a quantum…
We present the generation of high order harmonics in crystalline silicon subjected to intense near-infrared 30fs laser pulse. The harmonic spectrum extends from the near infrared to the extreme ultraviolet spectral region. Depending on the…
It is shown that under optimal conditions, the generation of the 3rd, 5th, 7th, and 9th harmonics of the short-wave, ultraviolet or vacuum ultraviolet, laser field by helium atoms is mainly due to transitions between bound states, and the…