Quantum control of the XUV photoabsorption spectrum of helium atoms via the carrier-envelope-phase of an infrared laser pulse

We examine above-threshold ionization spectra of model atomic hydrogen in short infrared laser pulses by solving the one-electron time-dependent Schr\“odinger equation in momentum space. To bypass the difficulty of solving the time-dependent Schr\”odinger equation with the interacting nonlocal Coulomb potential, we have recently formulated an alternative \emph{ab initio} approach [Ongonwou et al. Annals of Physics {\bf 375}, 471 (2016)], which is relied on the expansion of the atomic wavefunction and the interacting nonlocal Coulomb potential on a discrete basis set of Coulomb Sturmians in momentum space. As far as short infrared laser pulses are concerned, we have numerically evaluated the photoelectron momentum distributions, angular distributions and bound states populations. The results obtained from our accurate new computationally method are compared against predictions of other time-dependent calculations in the literature. This new theoretical model shows its sensitivity to the carrier-envelope phase of the laser pulse and captures the left-right dependence of the emitted photoelectrons momentum and angular distributions. More precisely, short pulses manifest significant dependence of the differential ionization probability on carrier-envelope phase of the laser pulse and broken forward-backward symmetry in the angular distributions.

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High-Resolution Photoabsorption Spectrum of Cs+ (5p61So + 5p5ns, nd) Between 504A and 600A using a Laser Ionized Cs Vapor Column

International Astronomical Union Colloquium ◽

10.1017/s0252921100085481 ◽

1984 ◽

Vol 86 ◽

pp. 124-124

Author(s):

T.J. McIlrath ◽

V. Kaufman ◽

J. Sugar ◽

W.T. Hill ◽

D. Cooper

Keyword(s):

High Resolution ◽

Laser Pulse ◽

High Voltage ◽

Power Output ◽

Random Phase ◽

Grazing Incidence ◽

Fano Resonances ◽

Line Shapes ◽

Phase Calculation ◽

Photoabsorption Spectrum

Rapid ionization of Cs vapor in a heat pipe at 0.05 torr was achieved by pumping the 6s 2S½ – 7p 2P½ transition (f=0.007)1 with a flash-pumped dye laser at 4593.2A and I MW power output. Photoabsorptian initiated at the end of the laser pulse(≃ 0.5/s) showed the 5p5ns and nd series below and above the 5p52P3/2 threshold at 535.4A. Broad Beutler - Fano resonances appeared in the d series above threshold. The spectrum was recorded photographically on a 10.7m grazing incidence spectrograph using a continuum background generated by a BRV high-voltage spark source with a uranium anode. We will compare the line-shapes and the quantum defect (Lu-Fano2) plot with the predictions of a relativistic random phase calculation.

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Signatures of the Carrier Envelope Phase in Nonlinear Thomson Scattering

Crystals ◽

10.3390/cryst11050528 ◽

2021 ◽

Vol 11 (5) ◽

pp. 528

Author(s):

Marcel Ruijter ◽

Vittoria Petrillo ◽

Thomas C. Teter ◽

Maksim Valialshchikov ◽

Sergey Rykovanov

Keyword(s):

Laser Pulse ◽

Radiation Spectrum ◽

Thomson Scattering ◽

High Energy ◽

Phase Changes ◽

High Energy Radiation ◽

Carrier Envelope Phase ◽

High Intensity Laser ◽

Experimental Parameters ◽

Intensity Laser

High-energy radiation can be generated by colliding a relativistic electron bunch with a high-intensity laser pulse—a process known as Thomson scattering. In the nonlinear regime the emitted radiation contains harmonics. For a laser pulse whose length is comparable to its wavelength, the carrier envelope phase changes the behavior of the motion of the electron and therefore the radiation spectrum. Here we show theoretically and numerically the dependency of the spectrum on the intensity of the laser and the carrier envelope phase. Additionally, we also discuss what experimental parameters are required to measure the effects for a beamed pulse.

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Characterizing the carrier-envelope phase stability of mid-infrared laser pulses by high harmonic generation in solids

Optics Express ◽

10.1364/oe.388465 ◽

2020 ◽

Vol 28 (12) ◽

pp. 17161

Author(s):

A. Leblanc ◽

P. Lassonde ◽

Gilles Dalla-Barba ◽

E. Cormier ◽

H. Ibrahim ◽

...

Keyword(s):

Harmonic Generation ◽

Phase Stability ◽

High Harmonic ◽

High Harmonic Generation ◽

Laser Pulses ◽

Infrared Laser ◽

Mid Infrared ◽

Carrier Envelope Phase

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Design of acousto–optic programmable filters in mercury halides for mid-infrared laser pulse shaping

Optics Communications ◽

10.1016/j.optcom.2008.04.002 ◽

2008 ◽

Vol 281 (15-16) ◽

pp. 4054-4056 ◽

Cited By ~ 8

Author(s):

Pierre Tournois

Keyword(s):

Laser Pulse ◽

Pulse Shaping ◽

Infrared Laser ◽

Mid Infrared ◽

Mercury Halides ◽

Laser Pulse Shaping

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Linear and nonlinear absolute phase effects in interactions of ulrashort laser pulses with a metal nano-layer or with a thin plasma layer

Laser and Particle Beams ◽

10.1017/s0263034607000250 ◽

2007 ◽

Vol 25 (3) ◽

pp. 379-390 ◽

Cited By ~ 14

Author(s):

S. Varró

Keyword(s):

Laser Pulse ◽

Phase Difference ◽

Plasma Layer ◽

Thin Foil ◽

Laser Pulses ◽

Thomson Scattering ◽

Carrier Envelope Phase ◽

Absolute Phase ◽

High Intensity Laser ◽

Order Of Magnitude

It has been shown that in the scattered radiation, generated by an ultrashort laser pulse impinging on a metal nano-layer, non-oscillatory wakefields appears with a definite sign. The magnitude of these wakefields is proportional to the incoming field strength, and the definite sign of them is governed by the cosine of the carrier-envelope phase difference of the incoming pulse. When we let such a Wakefield excite the electrons of a secondary target (say an electron beam, a metal surface or a gas jet), we can obtain 100 percent modulation in the electron signal in a given direction. This scheme can serve as a basis for the construction of a robust linear carrier-envelope phase difference meter. At relativistic laser intensities, the target is considered as a plasma layer in vacuum produced from a thin foil by a prepulse, which is followed by the main high-intensity laser pulse. The nonlinearities stemming from the relativistic kinematics lead to the appearance of higher-order harmonics in the scattered spectra. In general, the harmonic peaks are downshifted due to the presence of an intensity-dependent factor. This phenomenon is analogous to the famous intensity-dependent frequency shift in the nonlinear Thomson scattering on a single electron. In our analysis, an attention has also been paid to the role of the carrier-envelope phase difference of the incoming few-cycle laser pulse. It is also shown that the spectrum has a long tail where the heights of the peaks vary practically within one order of magnitude forming a quasi-continuum. Fourier synthesizing the components from this plateau region attosecond pulses has obtained.

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