Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-03T08:07:30.249Z Has data issue: false hasContentIssue false

Atomic, molecular, and photonic processes in laser-induced plasmas in alkali metal vapors

Published online by Cambridge University Press:  09 March 2009

William C. Stwalley
Affiliation:
Center for Laser Science and Engineering, Departments of Chemistry and Physics and Astronomy, University of Iowa, Iowa City, IA 52242
John T. Bahns
Affiliation:
Center for Laser Science and Engineering, Departments of Chemistry and Physics and Astronomy, University of Iowa, Iowa City, IA 52242

Abstract

The production of laser-induced plasmas, which ordinarily occurs only at high laser powers, occurs at far lower laser powers using resonant and collisional phenomena in alkali metal vapors. For example, 10 torr of Na vapor can be significantly ionized to produce a bright white ball with as little as 1 mW of focused cw dye laser power (e.g., at the 3p → 4d transitions at 568.3 and 568.8 nm). We first discuss the alkali metal vapors in general (1) and their important ionization processes (2), especially those occurring at photon energies below the atomic ionization energy. We then discuss the striking wavelength dependences of ionization. For example, cw laser irradiation of these vapors gives completely different behavior at slightly different wavelengths (Stwalley 1990): 10 torr of sodium vapor at 568.2 nm, where the vapor shows only molecular fluorescence and is sufficiently quiescent that highly stable, narrow-band, optically pumped lasers based upon the fluorescent transitions can easily be constructed (Bahns 1983; Bahns et al. 1983; Verma et al. 1983); and, at 568.3 nm, where a “quasiresonant” laser-induced plasma forms and strong emission (including violet excimer bands, a potential laser) is produced (Koch & Collins 1979; Bahns et al. 1989a; Bahns et al. 1989b). We will analyze and reinterpret the classic subthreshold ionization studies (3) and survey recent laser-induced plasma studies (4). We also discuss dissociative recombination and its selectivity for producing strong excimer emission (5) the predicted electronic spectra of the alkali metal molecular ions (6).

Type
Research Article
Copyright
Copyright © Cambridge University Press 1993

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Allegrini, M. et al. 1983 Phys. Rev. A 28, 199.CrossRefGoogle Scholar
Amiot, C. 1990 J. Chem. Phys. 93, 8591.CrossRefGoogle Scholar
Amiot, C. 1991 J. Mol. Spectroscop. 146, 370.CrossRefGoogle Scholar
Auerbach, D. et al. 1977 J. Phys. B 10, 3797.CrossRefGoogle Scholar
Bahns, J.T. 1983 Laser excitation studies of alkali metal vapors, Ph.D. thesis, University of Iowa.Google Scholar
Bahns, J.T. et al. 1983 Appl. Phys. Lett. 42, 336.CrossRefGoogle Scholar
Bahns, J.T. et al. 1989a Laser Particle Beams 7, 545.CrossRefGoogle Scholar
Bahns, J.T. et al. 1989b The Physics of Ionized Gases, Tanovic, L., Kanjevic, N., & Tanovic, N., eds. (Nova Science Publishers, Commack, NY), pp. 503515.Google Scholar
Bahns, J.T. et al. 1989c J. Chem. Phys. 90, 2841.CrossRefGoogle Scholar
Bearman, G.H. & Leventhal, J.J. 1978 Phys. Rev. Lett. 41, 1227.CrossRefGoogle Scholar
Bernheim, R.A. et al. 1983 J. Chem. Phys. 78, 3635.CrossRefGoogle Scholar
Bernheim, R.A. et al. 1984 Chem. Phys. Lett. 105, 201.CrossRefGoogle Scholar
Boody, F.B. & Prelas, M.A. 1990 In Advanced Solid State Lasers, Dubé, C. & Jenssen, H.P., eds. (Optical Society of America, Washington, DC), pp. 192199.Google Scholar
Borodin, V.M. et al. 1975 Opt. Spectroscop. 39, 231.Google Scholar
Bordas, C. et al. 1989 Chem. Phys. 129, 21.CrossRefGoogle Scholar
Bordas, C. et al. 1990 Phys. Rev. Lett. 64, 1223.CrossRefGoogle Scholar
Brechignac, C. & Cahuzac, P. 1985 Chem. Phys. Lett. 117, 365.CrossRefGoogle Scholar
Broyer, M. et al. 1983 Chem. Phys. Lett. 99, 206.CrossRefGoogle Scholar
Buhler, B. et al. 1992 Chem. Phys. Lett. 188, 247.CrossRefGoogle Scholar
Cerjan, C.J. et al. 1976 Chem. Phys. Lett. 38, 401.CrossRefGoogle Scholar
Cohen, E.R. & Taylor, B.N. 1990 Phys. Today 43, 9.Google Scholar
De Jong, A. & Van Der Valk, F. 1979 J. Phys. B 12, L561.Google Scholar
Dellwo, J. et al. 1992 Phys. Rev. A 45, 1544.CrossRefGoogle Scholar
Dobrolezh, B.V. et al. 1975 Opt. Spectroscop. 38, 630.Google Scholar
Dunne, S.J. et al. 1987 Spectrochim. Acta 43A, 699.CrossRefGoogle Scholar
Eaton, J.G. et al. 1992 Chem. Phys. Lett. 193, 141.CrossRefGoogle Scholar
Freudenberg, K. 1931 Z. Phys. 67, 417.CrossRefGoogle Scholar
Geltman, S. 1988 J. Phys. B 21, L735.CrossRefGoogle Scholar
Geltman, S. 1989 Phys. Rev. A 40, 2301.CrossRefGoogle Scholar
Gole, J.L. & Stwalley, W.C. 1982 Metal Bonding and Interactions in High Temperature Systems with Emphasis on Alkali Metals (American Chemical Society, Washington, DC).CrossRefGoogle Scholar
Gould, P.L. et al. 1988 Phys. Rev. Lett. 60, 788.CrossRefGoogle Scholar
Hayden, J.S. et al. 1986 J. Phys. Chem. 90, 1799.CrossRefGoogle Scholar
Hellfeld, A.V. et al. 1978 Phys. Rev. Lett. 40, 1369.CrossRefGoogle Scholar
Helm, H. & Möller, R. 1983 Phys. Rev. A 27, 2493.CrossRefGoogle Scholar
Helm, H. et al. 1983 J. Chem. Phys. 78, 6451.CrossRefGoogle Scholar
Henriet, A. 1985 J. Phys. B 18, 3085.CrossRefGoogle Scholar
Henriet, A. & Masnou-Seeuws, F. 1987 J. Phys. B 20, 671.CrossRefGoogle Scholar
Henderson, J.R. et al. 1988 Spectrochim. Acta 44a, 1287.CrossRefGoogle Scholar
Herrmann, A. et al. 1978 J. Chem. Phys. 68, 2327.CrossRefGoogle Scholar
Hotop, H. & Lineberger, W.C. 1985 J. Phys. Chem. Ref. Data 14, 731.CrossRefGoogle Scholar
Huennekens, J. & Gallagher, A. 1983 Phys. Rev. A 28, 1276.CrossRefGoogle Scholar
Huennekens, J. et al. 1985 Phys. Rev. A. 31, 196.CrossRefGoogle Scholar
Jeung, G. et al. 1990 Chem. Phys. Lett. 165, 494.Google Scholar
Jones, D.M. & Dahler, J.S. 1985 Phys. Rev. A 31, 210.CrossRefGoogle Scholar
Jones, D.M. & Dahler, J.S. 1988 Phys. Rev. A 37, 2916.CrossRefGoogle Scholar
Julienne, P.S. 1982 Chem. Phys. Lett. 87, 240.CrossRefGoogle Scholar
Julienne, P.S. & Heather, R. 1991 Phys. Rev. Lett. 67, 2135.CrossRefGoogle Scholar
Katern, A. et al. 1988 Chem. Phys. Lett. 146, 325.CrossRefGoogle Scholar
Keller, J. et al. 1986 Phys. Rev. A 33, 1612.CrossRefGoogle Scholar
Kim, B. & Yoshihara, K. 1993 Chem. Phys. Lett. 202, 437.CrossRefGoogle Scholar
Kirby-Docken, K. et al. 1976 Chem. Phys. Lett. 40, 205.CrossRefGoogle Scholar
Kircz, J.G. et al. 1982 Phys. Rev. Lett. 48, 610.CrossRefGoogle Scholar
Klucharev, A.N. et al. 1980 J. Phys. B 13, 1143.CrossRefGoogle Scholar
Klucharev, A.N. & Ryazanov, N.S. 1972 Opt. Spectroscop. 33, 230.Google Scholar
Klucharev, A.N. et al. 1977 Opt. Spectroscop. 42, 336.Google Scholar
Kniazzch, A.G.F. 1966 Bull. Am. Phys. Soc. 11, 634.Google Scholar
Knöckel, H. et al. 1991 Chem. Phys. 152, 399.CrossRefGoogle Scholar
Koch, M.E. & Collins, C.B. 1979 Phys. Rev. A 19, 1098.CrossRefGoogle Scholar
Koch, M.E. et al. 1980 J. Opt. Soc. Am. 70, 627.Google Scholar
Konowalow, D.D. & Fish, J.L. 1984 Chem. Phys. Lett. 104, 210.CrossRefGoogle Scholar
Kushawaha, V.S. & Leventhal, J.J. 1980 Phys. Rev. A 22, 2468.CrossRefGoogle Scholar
Kushawaha, V.S. & Leventhal, J.J. 1982 Phys. Rev. A 25, 346.CrossRefGoogle Scholar
Lawrence, E.O. & Edlefsen, N.E. 1929 Phys. Rev. 34, 233.CrossRefGoogle Scholar
Lee, Y.T. & Mahan, B.H. 1965 J. Chem. Phys. 12, 2893.CrossRefGoogle Scholar
LeGouët, J.L. et al. 1982 Phys. Rev. Lett. 48, 600.CrossRefGoogle Scholar
Lett, P.D. et al. 1991 Phys. Rev. Lett. 67, 2139.CrossRefGoogle Scholar
Leutwyler, S. et al. 1980 Chem. Phys. 48, 253.CrossRefGoogle Scholar
Lucatorto, T.B. & McIlrath, T.J. 1976 Phys. Rev. Lett. 37, 428.CrossRefGoogle Scholar
Lucatorto, T.B. & McIlrath, T.J. 1980 Appl. Opt. 19, 3948.CrossRefGoogle Scholar
Luh, W.T. et al. 1988 J. Chem. Phys. 88, 2235.CrossRefGoogle Scholar
Martin, S. et al. 1982 Chem. Phys. Lett. 87, 235.CrossRefGoogle Scholar
McGeoch, M.W. & Schlier, R.E. 1983 Chem. Phys. Lett. 99, 347.CrossRefGoogle Scholar
Measures, R.M. 1977 J. Appl. Phys. 48, 2673.CrossRefGoogle Scholar
Measures, R.M. et al. 1979 Appl. Opt. 18, 1824.CrossRefGoogle Scholar
Measures, R.M. & Cardinal, P.G. 1980 Phys. Rev. A 23, 804.CrossRefGoogle Scholar
Meijer, H.A.J. et al. 1987 Z. Phys. D 5, 299.CrossRefGoogle Scholar
Mitchell, J.B.A. et al. 1984 J. Phys. B 17, L909.CrossRefGoogle Scholar
Mohler, F.L. & Boeckner, C. 1930 J. Res. Natl. Bur. Std. 5, 51.CrossRefGoogle Scholar
Moore, C.E. 1971 Atomic Energy Levels (NSRDS - NBS 35) Vols. I-III.Google Scholar
Pichler, G. et al. 1986 Chem. Phys. Lett. 129, 145.CrossRefGoogle Scholar
Roussel, F. et al. 1981 J. Phys. B 14, L313.CrossRefGoogle Scholar
Schmidt-Mink, I. et al. 1985 Chem. Phys. 92, 263.CrossRefGoogle Scholar
Schwarz, M. et al. 1988 J. Chem. Phys. 89, 5460.CrossRefGoogle Scholar
Searles, D.J. et al. 1988a Spectrochim. Acta 44A, 505.CrossRefGoogle Scholar
Searles, D.J. et al. 1988b Spectrochim. Acta. 44A, 985.CrossRefGoogle Scholar
Stwalley, W.C. & Koch, M.E. 1980 Optic. Eng. 19, 71.CrossRefGoogle Scholar
Stwalley, W.C. 1990 In Proceedings of the Xth International Vavilov Conference on Nonlinear Optics, Novosibirsk (in press).Google Scholar
Stwalley, W.C. 1993 Private communication.Google Scholar
Sunil, K.K. & Jordan, K.D. 1984 Chem. Phys. Lett. 104, 343.CrossRefGoogle Scholar
Talbi, D. & Saxon, R. 1988 J. Chem. Phys. 89, 2235.CrossRefGoogle Scholar
Tam, A.C. & Happer, W. 1977 Opt. Comm. 21, 403.CrossRefGoogle Scholar
Tam, A.C. 1980 J. Appl. Phys. 51, 4682.CrossRefGoogle Scholar
Tam, A.C. 1982 In Metal Bonding and Interactions in High Temperature Systems, ACS Symposium Series 179, Gole, J.L. and Stwalley, W.C., eds. (American Chemical Society, Washington, DC), p. 447.CrossRefGoogle Scholar
Tsai, C.C. et al. 1992 Rev. Sci. Instrum. 63, 5576.CrossRefGoogle Scholar
Varandas, A.J.C. & Morais, V.M.F. 1982 Mol. Phys. 47, 1241.CrossRefGoogle Scholar
Verma, K.K. et al. 1983 J. Chem. Phys. 78, 3599.CrossRefGoogle Scholar
Veza, D. & Sansonetti, C.J. 1992 Z. Phys. D 22, 463.CrossRefGoogle Scholar
Wang, M.-X. et al. 1986a Phys. Rev. A 34, 1869.CrossRefGoogle Scholar
Wang, M.-X. et al. 1986b Phys. Rev. A 34, 4497.CrossRefGoogle Scholar
Wang, M.-X. et al. 1987 Phys. Rev. A 35, 934.CrossRefGoogle Scholar
Wang, M.-X. & Weiner, J. 1987 Phys. Rev. A 35, 4424.CrossRefGoogle Scholar
Weickenmeier, W. et al. 1985 J. Chem. Phys. 82, 5354.CrossRefGoogle Scholar
Weiner, J. et al. 1990 In Advances in Atomic Molecular and Optical Physics, Bates, D. and Bederson, B., eds. (Academic Press, New York), Vol. 26, pp. 209296.Google Scholar
Wu, C.H. 1976 J. Chem. Phys. 65, 3181.CrossRefGoogle Scholar
Xing, D. et al. 1991a Appl. Phys. Lett. 58, 1701.CrossRefGoogle Scholar
Xing, D. et al. 1991b J. Opt. Soc. Am. B 8, 917.CrossRefGoogle Scholar
Xing, D. et al. 1991c Rev. Laser Eng. 19, 46.CrossRefGoogle Scholar
Zemke, W. T. & Stwalley, W.C. 1993 J. Chem. Phys. (in press).Google Scholar