Experimental study of XUV laser produced plasma sheet for a microwave agile mirror application

Summary form only. An excimer-laser (/spl lambda/=193 nm, r=17 nS, E=20 mJ) along with a cylindrical lens system is utilized to produce a sheet plasma, in an organic gas (TMAE). The plasma has a peak density of 3.5/spl times/10/sup 13/ cm/sup -3/ and a "sheet" like profile of 0.2-0.7 cm/spl times/8 cm/spl times/20 cm. The effect of the lens system on the plasma, sheet thickness is examined. The triple probe measured plasma temperature (T/sub e//spl ap/1 eV) agrees with the postulation of single-photon absorption-ionization process. The plasma density spatial decay along the laser beam, which is associated with TMAE photon absorption length, is measured. The absorption length is found to be a function of base pressure of the neutral working gas. We have obtained an optimal window of TMAE base pressure at 50-150 mTorr. Within this optimal pressure range a plasma formation can have a long absorption length (L/sub a//spl ges/10 cm), relatively high plasma density (n/sub e//spl ges/5/spl times/10/sup 12/ cm/sup -3/), and lifetime of 5 /spl mu/s. A 1-D plasma diffusion model is proposed and solved both analytically and numerically. Comparison of the modeling and the measured results yields accurate values for the plasma diffusion and recombination coefficients.