Organic lasers, pumped

Iral modes within the narrow peak. However, mode structure was not observed in any of our measurements. Since both ASE and lasing are based on stimulated emission, the difference is not very important in the context of the electrically pumped organic laser. Moreover, because the distinction is not a key issue here, we consider the gain phenomena observed in systems without external feedback to be mirmrless lasing. 

MA Baldo, RJ Holmes, and SR Forrest, Prospects for electrically pumped organic lasers, Phys. Rev. B, 66 035320.1-035321.16, 2002. 

Finally, we note that 2 PA, and more generally simultaneous multi-photon absorption processes, has been used as a mechanism for pumping organic lasers using light available from semiconductor lasers [197-203]. 

Figure 145 (a) The cross-section of an edge emitting DL LED supposed to act as an electrically pumped organic laser (b) the molecular structure of Nile Blue (NB) and (c) the energy level diagram for the device. Adapted from Ref. 555. 

For several important applications in plastic optoelectronics, including the possibility of electrically pumped organic lasers, it would be very important to achieve an ambipolar operation in OFETs, with high electron and hole mobilities. Gate-controlled electroluminescence from organic small-molecule thin-film transistors... 

Liquid Organic solvent (dye-chromophore) Rhodamine dye (Rh6G) 580-610 Flashlamp laser pumping... 

Another example is the deactivation of high vibrational levels in the So and Si singlet states of dye molecules in organic liquids pumped by a pulsed laser (Fig. 6.98). The laser populates many vibrational levels in the excited Si singlet state, which are accessible by optical pumping on transitions starting from thermally populated levels in the electronic ground state So. These excited levels v )... 

The most intense 0-0 ZPLs of organic molecules of interest occupy the spectral range 650-250 nm. Thus, lasers for FLN. should be tunable within this range. The laser linewidth should match the FLN vibronic linewidth of the analytes, typically of the order of 1 - 3 cm . To avoid sample heating, saturation effects, and/or stimulated two-photon photoreactions, the average laser power should not exceed 1-lOmW. The cw dye lasers, pumped by Ar or ion lasers are relatively cheap and reliable sources for the visible spectrum. For UV, frequency-doubled dye lasers pumped by copper or quasi-continuous Nd-YAG lasers (typical repetition rates 1 -10 kHz) may be preferable. 

Examples here reviewed show the opportunity offered by a tight collaboration between supramolecular chemistry and physics to solve problems in emerging technologies such as those concerning OLED, OFET, OPV and sensors. In addition to these items, we suggest additional topics that deserve to be tackled in the near future, namely electrically pumped organic lasers and photonic crystals. 

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