Search

We demonstrate the highest intensity - 300 TW laser by developing booster amplifying stage to the 50-TW-Ti:sapphire laser (HERCULES). To our knowledge this is the first multi-100TW-scale laser at 0.1 Hz repetition rate.

Spectral-broadening of the APOLLON PW-class laser pulses using a thin-film compression technique within the long-focal-area interaction chamber of the APOLLON laser facility is reported, demonstrating the delivery of the full energy pulse to the target interaction area. The laser pulse at 7 J passing through large aperture, thin glass wafers is spectrally broadened to a bandwidth that is compatible with a 15-fs pulse, indicating also the possibility to achieve sub-10-fs pulses using 14 J. Placing the post-compressor near the interaction makes for an economical method to produce the shortest pulses by limiting the need for high damage, broadband optics close to the final target rather than throughout the entire laser transport system. [ABSTRACT FROM AUTHOR]

Interaction of relativistic intensity laser pulses encompassed at focus by a volume of a few wavelengths cubed with solids is examined. Spectroscopy of hard X-rays of several metallic targets, including Cu, Ge, Mo, Ag, and Sn, irradiated in this regime at a high repetition rate (0.4 kHz), has been experimentally studied. The Kα and Kβ peaks of all targets were obtained. Averaged electron temperatures of several tens of keV and total X-ray conversion efficiencies up to 0.02% are calculated. The X-ray source size is measured to be ∼10 micron with varying elliptical shape. [ABSTRACT FROM AUTHOR]

Using small amounts of optical energy, it is possible to drive matter with relativistic intensity. We show unique energy transport properties, X-ray production, and efficient attosecond phenomena coming from microscopic plasmas driven by precisely focused ultrashort pulses of light. [ABSTRACT FROM PUBLISHER]

We report on the generation and measurement of a > 108 contrast ratio between main pulse and amplified spontaneous emission (ASE) from a relativistic kHz chirped-pulse amplified laser. We have enhanced the ASE contrast ratio as much as > 400 times by employing a pulse cleaner composed of a μJ preamplifier and a saturable absorber. A third-order cross-correlator with a dynamic range of > 109 and a scanning range of up to 4 ns has been developed for the contrast measurement. Detailed analysis of the cross-correlation trace shows that the random noise of spectral phase generates 20-ps pedestal structure starting from 10−6 level of the main pulse. [ABSTRACT FROM AUTHOR]

Isolated attosecond pulses and electron bunches can be efficiently generated in the interaction of intense lasers with plasma in the confined volume of the λ3 regime. Scaling with intensity is found to improve pulse brevity and focusability greatly while the efficiency of the attosecond pulse generation continues to remain high. Practical consideration of the tools needed to generate such pulses indicates that such interactions are surprisingly accessible. We mention some introductory experiments whereby we may verify the theoretical predictions of this new class of attosecond pulses. This technique may enable us to reach the Schwinger intensity 1029 Wcm-2. [ABSTRACT FROM AUTHOR]

We demonstrate the enhancement of high-harmonic soft-X-ray generation by adaptive wave-front control of a 745-nm Ti:sapphire laser by use of a 59-channel membrane deformable mirror, combined with a genetic algorithm, for the first time to our knowledge. The harmonics ranging from 17 nm to 28 nm were enhanced by factors up to 13. The numerical calculations illustrate that the enhancements of the plateau harmonics are due to macroscopic phase-matching effect, whereas those of the cutoff harmonics are due to the increase in focal intensity. [ABSTRACT FROM AUTHOR]

The development of compact high-intensity lasers, made possible by the technique of chirped pulse amplification, is reviewed. This includes the complexities of high-power laser implementation, such as the generation of short pulses, pulse cleaning, wide-bandwidth amplification, temporal stretching and compression, and the requirements for high-average powers. Details of specific solid-state laser systems are given. Some applications of these lasers to short-pulse coherent short-wavelength [x-ray ultraviolet (XUV)] sources are also reviewed. This includes several nonlinear effects observed by focusing a subpicosecond laser into a gas; namely, an anomalous scaling of harmonic generation in atomic media, an upper limit on the conversion efficiency of relativistic harmonics in a plasma, and the observation of short-pulse self-focusing and multifoci formation. Finally, the effects of large ponderomotive pressures (100 Mbars) in short-pulse high-intensity laser-plasma interactions are discussed, with relevance both to recombination x-ray lasers and a novel method of igniting thermonuclear fusion. [ABSTRACT FROM AUTHOR]

The technique of chirped pulse amplification has revolutionized our ability to produce high-peak-power pulses. It is possible to produce with tabletop systems pulses in the 10-TW range and peak intensities in the 10[sup 19] to 10[sup 20] -W/cm[sup 2] range. With some refinements and with superior energy storage materials, even higher peak power in the petawatt range should be possible from tabletop systems. In this paper we show the ultimate achievable power and intensity, as well as their applications in science and technology. Their applications cover a wide variety of fields, such as precision surgery, micromachining, coherent and incoherent X-ray generation, thermonuclear ignition, particle acceleration, and nonlinear quantum electrodynamics. [ABSTRACT FROM AUTHOR]

The authors present a simple add on for multicycle, multimJ Ti:sapphire-based amplifier systems to efficiently generate 9.5 fs pulses with 1.8 mJ. Filamentary propagation yields spectrally broadened pulses carrying an unexpected large group-delay dispersion of -500 fs2 which allows linear propagation of the few-cycle pulses towards target areas without need of any sophisticated dispersion control. Pulse compression could easily be achieved by transmission through a combination of different glass substrates. The pulse wave front, the low energy fluctuations, and the good temporal contrast make this source well suited for relativistic laser-solid experiments with intense few-cycle pulses at kilohertz repetition rate. [ABSTRACT FROM AUTHOR]

Abstract. Since the inception of the laser, pulse duration has been continuously decreased by the use of a variety of techniques: Q-switching, mode-locking, and pulse compression. We would like to present a new technique based on the addition of laser sub-harmonic, ALS, that allows the production of a single-cycle pulse with single-femtosecond pulse duration. This simple technique takes advantage of the recent progress made in the generation of a few optical cycles and in optical parametric amplification. [ABSTRACT FROM AUTHOR]

We show that ring cavity regenerative amplifiers (regens) have distinct advantages over the linear ones for applications in chirped pulse amplification. Larger energy, better contrast and better isolation from the oscillator are experimentally demonstrated. [ABSTRACT FROM AUTHOR]

Two Yb3+-doped KGd(WO4)2 chirped-pulse regenerative amplifiers, one under direct diode pumping and the other under pulsed Ti:sapphire laser pumping, are demonstrated. A slope efficiency as great as 43% is achieved from the free-running bare cavity of the diode-pumped amplifier, and 72% from that of the Ti:sapphire-pumped. When injected, the diode-pumped amplifier produces 44 μJ, 390 fs pulses at 1 kHz, and the Ti:sapphire-pumped amplifier produces 16 mJ, 1 ps pulses at 1 Hz, following compression. [Copyright &y& Elsevier]