High temporal and spatial quality petawatt-class Ti:sapphire chirped-pulse amplification laser system

Abstract

Optical parametric chirped-pulse amplification (OPCPA) operation with low gain by seeding with high-energy, clean pulses is shown to significantly improve the contrast to better than 10(-10) to 10(-11) in a high-intensity Ti:sapphire laser system that is based on chirped-pulse amplification. In addition to the high-contrast broadband, high-energy output from the final amplifier is achieved with a flat-topped spatial profile of filling factor near 77%. This is the result of pump beam spatial profile homogenization with diffractive optical elements. Final pulse energies exceed 30 J, indicating capability for reaching peak powers in excess of 500 TW.

Efficient multi-keV X-ray generation from high-contrast laser plasma interaction

“…Refer to Refs. [7,8] for further details for the pulse shape. To investigate the influence of the contrast ratio on the K , the contrast ratio of the leakage pulse was varied from 10 −7 to 10 −11 by controlling the operation conditions of the pulse cleaner and the optical shutters in the front-end stage of the system.…”

Absolute Kα line spectroscopy for cone-guided fast-ignition targets

“…Absolute sensitivity for the Type-I setup was measured [6] at J-KAREN laser system at Japan Atomic Energy Agency, Kansai Photon Science Institute [7]. This system delivers a laser pulse of 800 nm wavelength, 1.8 J energy and 58 fs duration.…”

Laser Pulse Contrast Ratio Cleaning in 100 TW Scale Ti: Sapphire Laser Systems

“…For this measurement, part of the laser beam is usually sampled while the laser system is working at nominal energy or close to it. During the measurement, the last amplification stage can only be partly pumped, this does not significantly affect the final result as long as most of the amplification has been obtained (Kiriyama et al, 2010). The experimental set-up is described on figure 2.…”