Laser Action from Syn-(Methyl,methyl) Bimane
Abstract
At the present, the Coumarin laser dyes are the ones most widely used for the spectral region stretching from 440 to 550 nm. However, the Coumarin dyes have rather poor photochemical stability. While searching for more stable and efficient laser dyes, we studied 3,4,6,7-tetramethyl-1, 5-diazabicyclo(3.3. 0)octa-3, 6-diene-2, 8-dion (SYN-(CH3,Ch3)B for short). This new heterocyclic molecule was first reported by Kosower, Pazhenchevsky, and Hershkowitz in 1978. Their work included the observation of strong and striking fluorescence properties, as well as good photochemical stability, for these compounds. It should be emphasized that strong fluorescence (high quantum fluorescence yield) of organic compounds which are not benzene derivatives is rare. The quantum fluorescence yield of the syn-(R2,R1)B ranges from 0.7 to 0.9. The isomer anti- (R2,R1)B is only weakly fluorescent. There are two specific spectroscopic parameters of laser dyes which critically determine the laser action efficiency of flashlamp and cw laser-pumped dye lasers: (a) a high quantum fluorescence yield and (b) low triplet-triplet (T-T) absorption over the fluorescence (laser action) spectral region of the laser dye. We, therefore, recorded the T-T absorption spectrum of syn-(CH3,CH3)B. We compared the laser action parameters of syn-(CH3,CH3)B with those of Coumarin 30. Both syn-(CH3,CH3)B and Coumarin 30 showed laser action in the same spectral region. syn-(CH3,Ch3)B lased only 30% less efficient than did Coumarin 30. Reprints.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1986
- Accession Number
- ADA204800
Entities
People
- Chyn M. Lau
- I. R. Politzer
- Joseph H. Boyer
- Theodore G. Pavlopoulos