Abstract

We describe the design considerations and operating characteristics of a compact, widely tunable, narrow-linewidth, megawatt-class pulsed laser system based on Ti3+:Al2O3 (Ti:sapphire) pumped by the second harmonic of a 1.06µm Nd:YAG laser. The system delivers 10 mJ in a 5-ns near-transform-limited single-longitudinal-mode (SLM) pulse with a threshold of 20 mJ and a slope efficiency greater than 40%. By the technique of self-seeding, in which a portion of the gain medium’s spontaneous fluorescence is coupled back to the laser cavity, SLM operation may be obtained across the entire gain profile of Ti:sapphire with a minimum number of optical components and without external seeding.

© 1998 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. A. Kasapi, G. Y. Yin, and M. Jain, Appl. Opt. 35, 1999 (1996) and references therein; T. D. Raymond and A. V. Smith, Opt. Lett. 16, 33 (1991); injection seeding of a Nd:YAG laser oscillator is described in Y. K. Park, G. Guiliani, and R. L. Byer, Opt. Lett. 5, 96 (1980).
    [CrossRef] [PubMed]
  2. C. E. Hamilton, K. W. Kangas, C. H. Muller, and D. D. Lowenthal, Proc. SPIE 1223, 208 (1990).
    [CrossRef]
  3. K. Liu and M. G. Littman, Opt. Lett. 6, 117 (1981).
    [CrossRef] [PubMed]
  4. D. Ko, G. Lim, S. Kim, B. H. Cha, and J. Lee, Opt. Lett. 20, 710 (1995).
    [CrossRef] [PubMed]
  5. A. E. Siegman, Lasers (University Science, Mill Valley, Calif., 1986).
  6. G. A. Rines and P. F. Moulton, Opt. Lett. 15, 434 (1990).
    [CrossRef] [PubMed]

1996 (1)

1995 (1)

1990 (2)

G. A. Rines and P. F. Moulton, Opt. Lett. 15, 434 (1990).
[CrossRef] [PubMed]

C. E. Hamilton, K. W. Kangas, C. H. Muller, and D. D. Lowenthal, Proc. SPIE 1223, 208 (1990).
[CrossRef]

1981 (1)

Cha, B. H.

Hamilton, C. E.

C. E. Hamilton, K. W. Kangas, C. H. Muller, and D. D. Lowenthal, Proc. SPIE 1223, 208 (1990).
[CrossRef]

Jain, M.

Kangas, K. W.

C. E. Hamilton, K. W. Kangas, C. H. Muller, and D. D. Lowenthal, Proc. SPIE 1223, 208 (1990).
[CrossRef]

Kasapi, A.

Kim, S.

Ko, D.

Lee, J.

Lim, G.

Littman, M. G.

Liu, K.

Lowenthal, D. D.

C. E. Hamilton, K. W. Kangas, C. H. Muller, and D. D. Lowenthal, Proc. SPIE 1223, 208 (1990).
[CrossRef]

Moulton, P. F.

Muller, C. H.

C. E. Hamilton, K. W. Kangas, C. H. Muller, and D. D. Lowenthal, Proc. SPIE 1223, 208 (1990).
[CrossRef]

Rines, G. A.

Siegman, A. E.

A. E. Siegman, Lasers (University Science, Mill Valley, Calif., 1986).

Yin, G. Y.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (5)

Fig. 1
Fig. 1

Schematic diagram of the self-seeding laser system. The grazing incidence angle of the laser is 1.4°.

Fig. 2
Fig. 2

Gain-switching behavior between the coupled cavities with a laser gain cross section of 2.5×10-19 cm2 750 nm. The smaller, higher-loss Littman cavity (length, 21.5 cm; lifetime, 0.5 ns) saturates the gain quickly and seeds the longer cavity (length, 44 cm; lifetime, 1.5 ns). Points X, A, and B are described in the text.

Fig. 3
Fig. 3

Threshold and slope efficiency of the SLM (19.6 mJ, 43%) and BBL (23.5 mJ, 45%) configurations operating at 756 nm. Maximum possible slope efficiency is 70%. Inset: laser spectra of (a) the SLM and (b) the BBL configurations, indicating that the SLM can be achieved far from the peak free-running wavelength of the same mirror set. The emission cross section of Ti:sapphire peaks near 800 nm.

Fig. 4
Fig. 4

Pulse width of the SLM and the BBL configurations as a function of output pulse energy. The curves asymptotically approach their respective cavity lifetimes. The fit to the data indicates that the lifetime of the long cavity (BBL) is 4.5 ns, whereas that of the coupled cavity (SLM) is 3.5 ns. Inset: laser-oscillation buildup time, which is inversely proportional to the output pulse energy.

Fig. 5
Fig. 5

Spectrum analyzer scan of the single-mode laser output: 756-nm wavelength, 4-mJ pulse energy, 11-ns pulse width, 2-GHz etalon free spectral range (FSR). Inset: Gaussian fit to one of the modes, yielding a FWHM bandwidth of 118 MHz; the pulse-width–bandwidth product is 1.3.

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

MDW=LΔθ=N2λ22θλ=N2λ22d1cosθ,
dϕdt=lglcN*σcϕ-ϕτcGϕ,

Metrics