Tunable organic lasers

Tunable Organic Lasers Based on C-H Systems Incorporating DCM and DCM2 Molecules... 

M. Zavelani-Rossi, G. Lanzani, S. de Silvestri, M. Anni, G. GigU, R. Cingolani, G. Barbarella and L. Favaretto, Single-mode tunable organic laser based on an electroluminescent oligothiophene, App/. Phys. Lett., 79,4082-4084 (2001). 

Organic colors caused by this mechanism are present in most biological colorations and in the triumphs of the dye industry (see Azinedyes Azo dyes Eluorescent whitening agents Cyanine dyes Dye carriers Dyes and dye intert diates Dyes, anthraquinone Dyes, application and evaluation Dyes, natural Dyes, reactive Polymethine dyes Stilbene dyes and Xanthenedyes). Both fluorescence and phosphorescence occur widely and many organic compounds are used in tunable dye lasers such as thodamine B [81-88-9], which operates from 580 to 655 nm. 

The potential of a tunable dye laser should not be overlooked. A tunable dye laser, employing an organic dye as lasing material allows one to choose any suitable excitation line within a particular region. This is in contrast to the case of a gas ion laser which has a limited number of emission lines at fixed wavelength. Nevertheless, a tunable dye laser has significant drawbacks such as poor resolution imposed by the dye laser linewidth (1.2 cm-1) and a continuous background spectrum which requires the use of a tunable filter 15-18). 

The first, and still the most commonly used, of the tunable lasers were those based upon solutions of organic dyes. The first dye laser was developed by Sorokin and Lankard 05), and used a "chloro-aluminum phthalocyanine" (sic) solution. Tunable dye lasers operating throughout the visible spectrum were soon produced, using dyes such as coumarins, fluorescein, rhodamines, etc. Each dye will emit laser radiation which is continuously tunable over approximately the fluorescence wavelength range of the dye. 

Excitation of the Eu3+ or Tb3+ ions has traditionally been indirect, by broad-band UV excitation of a conjugated organic ligand which is followed by intramolecular energy transfer to the lanthanide ion / system, followed in turn by /- / emission.614 However, more recently, following the advent of tunable dye lasers, direct excitation of an excited / level is in many cases preferable. By scanning this frequency, an excitation spectrum can be obtained whose energy values are independent of the resolution of a monochromator and not subject to spectral interferences. 

K.I. (2007) Reaction optimisation and mechanism in maleimide photocycloaddition a dual approach using tunable UV laser and time-dependent DFT. Journal of Organic Chemistry, 72, 1449-1457. 

The active medium in tunable dye lasers is a dye solution. The dyes are organic compounds with conjugated double bonds and have delocalized n electrons... 

V. Sivaprakasam and D. K. Killinger, Tunable ultraviolet laser-induced fluorescence detection of trace plastics and dissolved organic compounds in water, Appl. Opt. 42,6739-6746 (2003). 

Time-resolved infrared spectroscopy (TRIR) has been outstandingly successful in identifying reactive intermediates and excited states of both metal carbonyl [68,69] and organic complexes in solution [70-72]. Some time ago, the potential of TRIR for the elucidation of photochemical reactions in SCFs was demonstrated [73]. TRIR is particularly suited to probe metal carbonyl reactions in SCFs because v(CO) IR bands are relatively narrow so that several different species can be easily detected. Until now, TRIR measurements have largely been performed using tunable IR lasers as the IR source and this has restricted the application of TRIR to the specialist laboratory [68]. However, recent developments in step-scan FTIR spectroscopy promise to open up TRIR to the wider scientific community [74]. 

Webb, J. Pierce, Tunable Organic Dye Lasers, Anal. Chem., 44, 30A (1972). 

Key CL, chemiluminescence UV, ultraviolet IR, infrared FTIR, Fourier-transform infrared spectroscopy TOLAS, tunable diode laser absorption spectroscopy IDS, indigo-5,5 -disulfon-ate ASTM, American Society for Testing and Materials ERA, US Environmental Protection Agency approved methods JIS, Japanese Industrial Standard WHO, World Health Organization selected methods n.a., not available. 

Woggon, T, Klinkhammer, S., and Lemmer, U. (2010) Compact spectroscopy system based on tunable organic semiconductor lasers. Appl. Phys. B, 99,... 

F.J. Duarte Tunable Organic Dye Lasers. Prog. Quantum Electron. 36, 29 (2012)... 

Strangi G, Bama V, Caputo R, Luca AD, Versace C, Scaramuzza N, Umeton C, Bartolino R, Price GN (2005) Color-tunable organic microcavity laser array using distributed feedback. Phys Rev Lett 94 063903-1-063903 ... 

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