Title :
Laser-driven ion sources for high-brightness high-purity ion beams
Author :
Filuk, A.B. ; Ching, C.H. ; Cuneo, M.E. ; Bailey, J.E. ; Bernard, M.A. ; Clark, B.F. ; Fowler, William E. ; Lake, P. ; Lash, J.S. ; McKenney, J. ; Menge, P.R. ; Cohen, David ; Wang, Peng
Author_Institution :
Sandia Nat. Labs., Albuquerque, NM, USA
Abstract :
Summary form only given. Surface-plasma ion sources are critical to generating high-brightness, high purity ion beams on applied-B ion diodes. The source plasma must meet requirements for species, thickness, purity, degree of conductivity, formation timescale, and feasibility. Laser ionization schemes have been used on high-power ion diodes with encouraging but inconsistent results in diode impedance and beam purity. We are characterizing two laser-driven Li/sup +/ schemes for 100-200 cm/sup 2/ sources: a single 10 ns Nd:YAG pulse at 0.3-1 J/cm/sup 2/, or the 2-laser LEVIS scheme. Recognizing anode surface contamination as a key issue in 10/sup -5/-10/sup -6/ Torr pulsed power vacuum, we subject well-characterized 0.5 /spl mu/m LiAg films on stainless substrates to extended 150-400/spl deg/C heating and plasma discharge sputter cleaning after pumpdown in a test chamber, prior to pulsing the source lasers. A detailed diagnostic set includes absolutely-calibrated, streaked, CCD-imaged spectrographs for plasma properties, 2-color laser deflection for plasma/neutral expansion, ion time-of-flight spectrograph with ionizer for species content, and a tunable narrow-band dye laser for near-resonant absorption.
Keywords :
ion beams; ion sources; ionisation; plasma diagnostics; plasma diodes; plasma production; plasma production by laser; 150 to 400 C; 1E-5 to 1E-6 torr; 2-color laser deflection; LEVIS scheme; LiAg films; absolutely-calibrated streaked CCD-imaged spectrographs; anode surface contamination; applied-B ion diodes; conductivity; diagnostic set; formation timescale; heating; high-brightness high-purity ion beams; ion time-of-flight spectrograph; laser ionization schemes; laser-driven Li/sup +/ schemes; laser-driven ion sources; plasma discharge sputter cleaning; plasma/neutral expansion; pulsed power vacuum; stainless substrates; surface-plasma ion sources; tunable narrow-band dye laser; Conductivity; Diodes; Ion beams; Ion sources; Ionization; Optical pulses; Plasma diagnostics; Plasma properties; Plasma sources; Pump lasers;
Conference_Titel :
Plasma Science, 1997. IEEE Conference Record - Abstracts., 1997 IEEE International Conference on
Conference_Location :
San Diego, CA, USA
Print_ISBN :
0-7803-3990-8
DOI :
10.1109/PLASMA.1997.604364
