Solid-state dye lasers based on modified rhodamine 6G dyes copolymerized with methacrylic monomers

Abstract

Modified rhodamine 6G molecules with polymerizable double bonds have been copolymerized with methacrylic monomers and the resulting polymers have been pumped at 337 nm with a N 2 laser in a transversal configuration. The preparation of these new materials is described in detail and their lasing properties are evaluated. Important increases in photostability, with lasing efficiencies similar to those found for the parent dye rhodamine 6G in ethanol solution, have been obtained for some of these materials. Lifetimes ͑measured as an 80% efficiency drop͒ in excess of 20 000 shots at repetition rates of 2 Hz have been demonstrated. Strong dependence on pump repetition rate was observed. Possible mechanisms and processes responsible for the behavior of these materials are discussed. By using a rotating system where the sample is scanned in a continuous way, the laser output remained stable, with no sign of degradation, after 500 000 shots.

Obtención de nuevos materiales híbridos orgánico-inorgánicos fotosensibles utilizables como láseres de colorante en estado sólido

“…Sin embargo, también han sido descritas mayores eficiencias para el PM567 en xerogeles, en cuyo caso la eficiencia láser obtenida variaba desde el 29% hasta alcanzar valores del 66%, dependiendo del tipo de cavidad óptica de colorante empleada y de los parámetros de bombeo láser (16,17). Es importante resaltar el hecho de que en todos los casos referenciados el bombeo de láser era longitudinal y la reflectividad del acoplador de salida estaba optimizada, mientras que los resultados obtenidos en el presente trabajo resultan de bombeo láser transversal, sin optimizar la cavidad resonante.…”

“…No obstante, recientemente se han obtenido nuevos polí-meros modificados con umbrales de daño respecto a la radiación láser tan altos como los de los materiales inorgánicos, y con estabilidades comparables o superiores a las de los geles de sílice bajo las mismas condiciones experimentales (16)(17)(18). Los polímeros presentan, además, otras ventajas importantes sobre los geles de sílice, tales como una mayor capacidad para disolver los colorantes orgánicos, una homogeneidad óptica superior (19) (lo que es extremadamente importante para el desarrollo de osciladores láser de pequeña anchura de línea) y una adaptabilidad a técnicas de fabricación económicamente más favorables (lo que facilitaría la miniaturización y el diseño de sistemas ópticos integrados).…”

Studying the Linear and Nonlinear Optical Properties by Using Z-Scan Technique for CdS Thin Films Prepared by CBD Technique

“…The two nonlinear interactions that can be determined in this fashion are the sample's nonlinear index of refraction and nonlinear absorption coefficient (Sheik-Bahae & Hasselbeck, 2000). To detect the nonlinear properties as the absorption coefficient and the nonlinear refractive index, there are two methods, each of which is calculated as one of them depending on the other : (i) The geometry in which a finite aperture is kept before the detector is known as a closed-aperture (CA) Z-scan; (ii) the geometry in which the aperture is removed to focus all the transmitted light into the detector is referred to as an open-aperture (OA) Z-scan (Costela et al, 1996;Hutchings, Sheik-Bahae, Hagan, & Van Stryland, 1992;Chari et al, 1996). The main principle of zscan technique is based on transforming the phase distortion to amplitude distortions during beam propagation (Sheik-Bahae, Said, & Van Stryland, 1989).…”

Two-dimensional polymer photonic crystal band-edge lasers fabricated by nanoimprint lithography

“…The laser emission drops exponentially to 10% of its initial values after 8200 pulses, which is comparable to solid-state dye lasers emitting in the visible wavelengths. 24 To improve the lifetime of the lasers, a solution is to replace the dye molecules with semiconductor nanocrystals with optical gain 25 embedded in a printable polymer. 20 In summary, two-dimensional polymer photonic crystal band-edge lasers fabricated by nanoimprint lithography have been realized.…”