Experimental study of neonlike zinc J=0-1 soft X-ray lasing at 21.2 nm
- Laboratoire de Spectroscopie Atomique et Ionique, URA 775 CNRS, Universite Paris-Sud, Batiment 350, 91405 Orsay Cedex (France)
Since our first observation of intense J=0-1 lasing in neonlike zinc in early 1993, we have investigated various issues of this X-ray laser. The results of these experiments, performed at Laboratoire pour l'Utilisation des Lasers Intenses (LULI), are briefly reviewed. Gain coefficients of {approx}5 cm{sup -1} at 21.2 nm are now routinely obtained with {approx_equal}350 J delivered onto a Zn slab in {approx}650 ps pulses--the net irradiance is {approx}1.4x10{sup 13} W cm{sup -2}. The 21.2 nm emission appears in a {approx_equal}100 ps burst and precedes the lasing on the J=2-1 transitions at 26.2 and 26.7 nm which have a duration {approx_equal}350 ps. We have directly measured the gain regions of the J=0-1 line at 21.2 nm and the J=2-1 line at 26.7 nm and confirmed the initial claim that they are located at different distances from the target. We have also measured the refraction angles and divergences of the XRL beams of these two transitions. The beam at 21.2 nm was observed to be remarkably narrow with a divergence of {approx}2.6 mrad, peaking {approx}7 mrad off-axis. This contrasts to the beam at 26.7 nm which has a divergence of {approx_equal}10 mrad and peaks at {approx}15 mrad. The most recent finding is that the J=0-1 lasing exists only when the main pump pulse is preceded by a pulse train of mJ level, which is a remnant from the laser oscillator. An important achievement in developing the XRL at 21.2 nm was the demonstration of half-cavity operation: with a gain-length product of {approx}16.5, the emission exhibits saturation behavior. The absolute energy measurements indicate {approx}400 {mu}J in the near-saturated beam.
- OSTI ID:
- 21153828
- Journal Information:
- AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 332; ISSN APCPCS; ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Sensitivity of lasing in neonlike zinc at 21. 2 nm to the use of the prepulse technique
High gain-production efficiency and large brightness X-UV laser at Palaiseau