Rhodamine 6G laser

Figure 5.12. Rhodamine 6G laser dye (open powder, Exciton), observed with conditions of Figure 5.9, except average of twenty 0.2 sec integrations. Both spectra are response corrected, but lower spectrum is after a linear baseline was subtracted.

An etalon is used for single-mode selection in a 1-m rhodamine 6G laser. If the dye gain bandwidth is commensurate with the width of the rhodamine 6G fluorescence spectrum shown in Problem 8.2, what etalon separations and etalon surface reflectivities would ensure that only one axial mode is selected at any time ... 

Figure Bl.22.7. Left resonant seeond-hannonie generation (SHG) speetnimfrom rhodamine 6G. The inset displays the resonant eleetronie transition indueed by tire two-photon absorption proeess at a wavelength of approximately 350 mn. Right spatially resolved image of a laser-ablated hole in a rhodamine 6G dye monolayer on fiised quartz, mapped by reeording the SHG signal as a fiinetion of position in the film [55], SHG ean be used not only for the eharaeterization of eleetronie transitions within a given substanee, but also as a mieroseopy tool.

Organic Dye Lasers. Organic dye lasers represent the only weU-developed laser type in which the active medium is a Hquid (39,40). The laser materials are dyestuffs, of which a common example is rhodamine 6G [989-38-8]. The dye is dissolved in very low concentration in a solvent such as methyl alcohol [67-56-17, CH OH. Only small amounts of dye are needed to produce a considerable effect on the optical properties of the solution. 

ESO VLT/Max Planck CW Dye Laser. The MPI is developing a CW dye laser for deployment on one ESO 8-m VLT telescope in 2004 (Eig. 13). The oscillator is a Coherent 899 ring dye laser, with a 2-5 W output, pumped by a 10 W, Coherent Verdi frequency-doubled Nd YAG laser. The beam is amphfied in a four-pass amphfier with 4 high velocity dye jets pumped with 4 10 W Verdi lasers. The system utihzes Rhodamine 6G in ethylene glycol however, because of the high pump power, the dye degrades quickly, and must... 

Figure 1.19 Energy levels and transitions in the rhodamine 6G dye laser...

Fig. 3 (a) Normalized excitation and emission spectra of 5-(and-6)-carboxy-fluorescein, succini-midyl ester, rhodamine 6G (R6G), and 6-carboxy-X-rhodamine dyes in pH 7.4 phosphate buffer, (b) Confocal fluorescence image of a mixture of five types of microsphere-DDSN complexes under 488-nm Argon-ion laser excitation. Reproduced with permission from Ref. [12]... 

Rhodamines (e.g. rhodamine 6G, rhodamine B) were among the first fluorescent dyes to be used as laser dyes. In contrast to coumarins, their absorption and emission spectra are quite narrow and the Stokes shift is small. They emit fluorescence in the range 500-700 nm. 

The time behaviour of triplet-state absorption of illuminated Rhodamin 6G dye molecules, which plays a fundamental role in dye lasers, has been studied by several authors 165b)... 

The most important xanthenes are the imino derivatives known as rhodamines, exemplified by rhodamine B (Cl Basic Violet 10) (3.23a), A. 543 nm and 552 nm and rhodamine 6G (Cl Basic Red 1) (3.23b), /L 530 and X 557 nm (Figure 3.11). These are intensively fluorescent dyes with quantum yields close to unity. Rhodamine 6G especially has found wide apphcation in dayhght fluorescent pigments (see section 3.5.2) and this ring structure has been much modified for use in many other outlets, especially as laser dyes (see section 3.5.3) and in biomedical applications (see section 3.5.6). 

Laser dye/Si02 gel CT AB/decanol/decane/ formamide (nonaqueous xE) TE0S/H20 (pH 1, HNO 3 10-2 M laser dye) Silica gels doped with laser dyes (rhodamine B, rhodamine 6G) gave fluorescence quantum yields indicating promise as candidate solid-state laser dye materials (49)... 

In another picosecond laser study of Forster energy transfer, Sato et al. [165] have studied systems of rhodamine 6G (R6G) and/or 3,3 -diethyl-thiacarbocyanine iodide (DODCI). Satisfactory agreement between the experimentally observed decay of R6G fluorescence and that based on the Forster kinetics [eqn. (85) with a calculated R0 — 5.9 nm and r = 0] was noted. However, from eqn. (85), Uiim 10-9 m2 s-1, so that Forster... 

Fluorescence depolarisation by energy transfer (rather than rotational relaxation) between donor molecules of the same type can occur. Eisenthal [174] excited solutions of rhodamine 6G (9 mmol dm-3) in glycerol with 530 nm light from a frequency-doubled neodymium laser. The polarisation... 

A crucial part of these experiments is the preparation of the sodium atoms into the excited state by laser optical pumping. A commercial single-mode Rhodamin 6G continuous wave (cw)-dye laser (Spectra Physics model 580) is used, having 20-40-mW single mode output power when tuned to the sodium resonance line. 

The main advantages of dye lasers are spectrum coverage (from less than 400 to 1000 nm) and tunability. In general, the laser dyes used nowadays have changed little from those used a decade ago [3]. Coumarins such as (73) and xanthenes such as Rhodamine 6G (74), are the main types. However, fluorinated coumarin dyes such as (75) have higher light stability than their nonfluorinated counterparts [39],... 

Most of the research over the past twenty years has been aimed at improving the performance of dye lasers by incorporating the laser dyes into a solid matrix [63], The choice of dye has the biggest effect on performance, with pyrromethine dyes having the best performance [64], Dyes such as Rhodamine 6G and Coumarin 540A have also been incorporated into an acrylic polymer matrix [65],... 

Time-resolved fluorescence was used to detect rhodamine 6G (R6G), sulfor-hodamine 101 (SR101), and rhodamine B (RB). A Ti-sapphire laser (800 nm, 50 fs) was used, but the excitation wavelength has been converted to 400 nm (for R6G) or 532 nm (for SR 101 or RB) by an optical parametric amplifier or by second harmonic generation [676], In another report, fluorescence burst detection was used for detection of single chromophore molecules [677]. 

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