相关论文: Central frequency of few-cycle laser pulses in str…
We demonstrate experimentally and theoretically a controllable way of shifting the frequency of an optical pulse by using a combination of spectral hole burning, slow light effect, and linear Stark effect in a rare-earth-ion doped crystal.…
A mechanism is explored whereby intense laser radiation induces an optical force between the constituent atoms of a molecule. In the case of a diatomic molecule the effect results in a modification of the vibrational potential, and using…
Strong-field phenomena driven by an intense infrared (IR) laser depend on during what part of the field cycle they are initiated. By changing the sub-cycle character of the laser electric field it is possible to control such phenomena. For…
Compton scattering of short and ultra short (sub-cycle) laser pulses off mildly relativistic electrons is considered within a QED framework. The temporal shape of the pulse is essential for the differential cross section as a function of…
Precise control of the electron phase accumulated during its sub-cycle motion within intense laser fields is essential in strong-field physics, yet remains mostly indirect and complicated so far. In this Letter, we develop a novel approach…
The advent of visible-infrared laser pulses carrying a substantial fraction of their energy in a single field oscillation cycle has opened a new era in the experimental investigation of ultrafast processes in semiconductors and dielectrics…
We experimentally investigate fluctuations in the spectrum of ultrashort laser pulses propagating in air, close to the critical power for filamentation. Increasing the laser peak power broadens the spectrum while the beam approaches the…
A detailed analysis of the photon emission spectra of an electron scattered by a laser pulse containing only very few cycles of the carrying electromagnetic field is presented. The analysis is performed in the framework of strong-field…
The serrodyne principle enables shifting the frequency of an electromagnetic signal by applying a linear phase ramp in the time domain [1]. This phenomenon has been exploited to frequency-shift signals in the radiofrequency (RF), microwave…
The knowledge of the frequency noise spectrum of a diode laser is of interest in several high resolution experiments. Specifically, in laser-pumped vapor cell clocks, it is well established that the laser frequency noise plays a role in…
We introduce an alternative definition of the main frequency of an ultrashort laser pulse, the principal frequency $\omega_P$. This parameter is complementary to the most accepted and widely used carrier frequency $\omega_0$. Given the fact…
When an intense, few-cycle light pulse impinges on a dielectric or semiconductor material, the electric field will interact nonlinearly with the solid, driving a coherent current. An asymmetry of the ultrashort,…
The use of strong-field (i.e. intensities in excess of 10^13 Wcm-2) few-cycle ultrafast (durations of 10 femtoseconds or less) laser pulses to create, manipulate and image vibrational wavepackets is investigated. Quasi-classical modelling…
We report on the generation of optical vortices with few-cycle pulse durations, 500$\mu$J per pulse, at a repetition rate of 1 kHz. To do so, a 25 fs laser beam at 800 nm is shaped with a helical phase and coupled into a hollow core fiber…
We find that, for sufficiently strong mid-IR fields, transitions between different conduction bands play an important role in the generation of high-order harmonics in a dielectric. The transitions make a significant contribution to the…
The effects of the discharge voltage on the formation and nature of electric field transients in a symmetric, collisionless, very high frequency, capacitively coupled plasma are studied using a self-consistent particle-in-cell (PIC)…
The effect of the frequency chirping on momentum spectrum and pair production rate in one- and two-color laser pulse fields is investigated by solving the quantum Vlasov equation. A small frequency chirp shifts the momentum spectrum along…
This paper will deal with isolated laser pulses, those which last for a finite time interval and whose envelope function is strictly zero outside of this interval. We numerically calculate the Fourier transform of this function and study…
It is shown that in many-electron systems quantum transfer amplitudes and thus transfer probabilities may be strongly influenced by fast fluctuating fields, in particular, caused by simultaneous electron transfers. Corresponding mutual…
Analytic expressions for the electromagnetic fields of an ultrashort, tightly focused, linearly polarized laser pulse in vacuum are derived from scalar and vector potentials, using a small parameter which assumes a small bandwidth of the…