BROADLY TUNABLE CONTINUOUS-WAVE LASER USING COLOR CENTERS
 Inventor: Linn Frederick Mollenauer, Colts Neck, N.J.
 Assignee: Bell Telephone Laboratories,
Incorporated, Murray Hill, NJ.
 Filed: Mar. 3, 1975
 Appl. No.: 554,467
Related U.S. Application Data
 Continuation-in-part of Ser. No. 438,200, Jan. 31, 1974, abandoned.
 U.S. CI 331/94.5 F; 330/4.3
 Int. CI.2 H01S 3/16
 Field of Search 331/94.5; 330/4.3;
 References Cited
UNITED STATES PATENTS
3,447,138 5/1969 Carson et al 340/173
3,753,148 8/1973 Billman 331/94.5
OTHER PUBLICATIONS Fritz et al., Laser Effect in KCL with F^(Li) Centers, Solid State Communications, vol. 3, No. 3, (1965), pp. 61-63.
Physics of Color Centers, Edited by Fowler, Academic Press, N.Y., (1968), pp. 182-242.
Bloom, Modes of a Laser Resonator Container Tilted Birefringent Plates, JOSA, vol. 64, No. 4, (Apr. 1974), pp. 447-452.
Primary Examiner—William L. Sikes
Attorney, Agent, or Firm—W. L. Wisner
Broadly tunable infrared lasers analogous to dye lasers operating in the visible spectrum are provided by significant improvements upon an F^(II) color center laser previously demonstrated in a limited way. The improvements include techniques for also using FB(II) and F2 +color centers and include substantially increased concentrations of the F-centers in regions of pumpable geometry, judicious choice of pumping frequencies and powers and variable, frequency-selecting resonators that are capable of producing oscillation anywhere in the color center fluorescence bands. All solid-state cooling by means of contact between the crystal and a solid heat sink is provided in a way that provides the optical quality needed for efficient operation and for greatest tuning bandwidth of the laser. Use of the color centers in distributed feedback devices is described.