Related papers: Bound electron nonlinearity beyond the ionization …
We directly measure the nonlinear optical response in argon and nitrogen in a thin gas target to laser intensities near the ionization threshold. No instantaneous negative nonlinear refractive index is observed, nor is saturation, in…
Ionization of atoms and molecules in strong laser fields is a fundamental process in many fields of research, especially in the emerging field of attosecond science. So far, demonstrably accurate data have only been acquired for atomic…
The balance of the linear photon momentum in multiphoton ionization is studied experimentally. In the experiment argon and neon atoms are singly ionized by circularly polarized laser pulses with a wavelength of 800 nm and 1400 nm in the…
The electronic, rotational, and vibrational components of the ultrafast optical nonlinearity in H$_2$ and D$_2$ are measured directly and absolutely at intensities up to the ionization threshold of $\sim$10$^{14}$ W/cm$^2$. As the most…
We present a detailed experimental and theoretical study on the relativistic non-dipole effects in strong-field atomic ionisation by near-infrared linearly-polarised few-cycle laser pulses in the intensity range 1014 -1015 W/cm2. We record…
The process of nonlinear electron emission from a metal surface under the action of femtosecond laser pulse with moderate intensity $\sim10^{11}$~W/cm$^2$ is considered. One-dimensional model is formulated, taking into account the advantage…
We investigate the carrier-envelope phase and intensity dependence of the longitudinal momentum distribution of photoelectrons resulting from above-threshold ionization of argon by few-cycle laser pulses. The intensity of the pulses with a…
We present the first experimental observation of above-threshold ionization (ATI) electrons produced by ionization of the neon K-shell in a laser field where intensity exceeds 10$^{20}$ W/cm$^{2}$. An array of plastic scintillating…
We revisit the stabilization of ionization of atoms subjected to a superintense laser pulse using nonlinear dynamics. We provide an explanation for the lack of complete ionization at high intensity and for the decrease of the ionization…
We present experimental results for the ionization of aniline and benzene molecules subjected to intense ultrashort laser pulses. Measured parent molecular ions yields were obtained using a recently developed technique capable of…
Intense extreme-ultraviolet (XUV) pulses enable the investigation of XUV-induced nonlinear processes and are a prerequisite for the development of attosecond pump - attosecond probe experiments. While highly nonlinear processes in the XUV…
Modern intense ultrafast pulsed lasers generate an electric field of sufficient strength to permit tunnel ionization of the valence electrons in atoms. This process is usually treated as a rapid succession of isolated events, in which the…
We report on the experimental studies of laser driven ion acceleration from double-layer target where a near-critical density target with a few-micron thickness is coated in front of a nanometer thin diamond-like carbon foil. A significant…
Ionization by relativistically intense laser pulses of finite duration is considered in the framework of strong-field quantum electrodynamics. Our main focus is on the formation of ionization supercontinua. More specifically, when studying…
The alignment dependence of the ionization behavior of H$_2$ exposed to intense ultrashort laser pulses is investigated on the basis of solutions of the full time-dependent Schr\"odinger equation within the fixed-nuclei and dipole…
Ionization of hydrogen-like ions by intense, circularly polarized laser pulses is analyzed under the scope of the relativistic strong-field approximation. We show that, for specific parameters of the laser field, the energy spectra of…
We experimentally investigate the generation of above-threshold harmonics completely from argon atoms on an excited state using mid-infrared femtosecond laser pulses. The highly nonlinear dependences of the observed signal on the pulse…
The first ionization potential of neutral atoms is determined from thresholds of laser-induced optical breakdown. Bulk material ablation plasma of aluminum, silver, lead, indium and copper is created in laboratory air with focused, 5-ns…
The process of ionization of a hydrogen atom by a short infrared laser pulse is studied in the regime of very large pulse intensity, in the dipole approximation. Let $A$ denote the integral of the electric field of the pulse over time at…
We present measurements of integrated electron energies produced by above-threshold ionization (ATI) of neon in a laser field with intensity exceeding 10$^{20}$ W/cm$^{2}$. We observe electrons with energy exceeding 10 MeV ejected in the…