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R Sastre - One of the best experts on this subject based on the ideXlab platform.
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photo physical characterization of Rhodamine 6G in a 2 hydroxyethyl methacrylate methyl methacrylate copolymer
Chemical Physics, 2000Co-Authors: W Holzer, Alfons Penzkofer, H Gratz, T Schmitt, A Costela, I Garciamoreno, R Sastre, F J DuarteAbstract:Abstract Some photo-physical parameters of 1×10−4 and 5.9×10−4 M samples of Rhodamine 6G in a 2-hydroxyethyl-methacrylate methyl-methacrylate copolymer (volume mixture 1:1) are determined and compared with Rhodamine 6G in methanol. They include the absorption cross-section and stimulated emission cross-section spectra, the fluorescence quantum distributions, quantum yields and lifetimes. The photo-degradation under steady-state and pulsed excitation is investigated. The saturable absorption behaviour under picosecond laser excitation is studied.
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internal photostabilization of polymeric solid state dye lasers based on trichromophoric Rhodamine 6G molecules
Chemical Physics Letters, 1997Co-Authors: A Costela, I Garciamoreno, F Amatguerri, He Tian, K Chen, M L Carrascoso, J Barroso, R SastreAbstract:Abstract We report on the lasing action of a modified Rhodamine 6G dye with two covalently bonded identical 1,8-naphthalimide groups in liquid solution in ethanol and in solid solutions in a methacrylate copolymer. When the solid samples are transversely pumped with 534 nm pulses at a repetition rate of 1 Hz, we have observed that the presence of the naphthalamide groups results in a clear photostabilization of the material. Possible mechanisms for the photostabilization process are suggested.
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solid state dye lasers based on modified Rhodamine 6G dyes copolymerized with methacrylic monomers
Journal of Applied Physics, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, Ricardo Mallavia, M D Santamaria, R SastreAbstract: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 N2 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 drop) 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.
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solid state dye lasers based on polymers incorporating covalently bonded modified Rhodamine 6G
Applied Physics Letters, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, R SastreAbstract:We report on the lasing action of modified Rhodamine 6G dyes copolymerized with methacrylic monomers. The laser samples were transversely pumped with a N2 laser at 337 nm. Lasing efficiencies similar to those found for Rhodamine 6G in ethanol solution have been achieved. Important increases in photostability, with lifetimes in excess of 20 000 shots at 2 Hz, have been obtained. By using a rotating mechanism, a stable output with no sign of degradation after half a million shots has been demonstrated.
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solid state dye lasers based on copolymers of 2 hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G
Applied Physics B, 1995Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, F Florido, R Duchowicz, R SastreAbstract:Rhodamine 6G has been dissolved in copolymers of 2-HydroxyEthyl MethAcrylate (HEMA) and Methyl MethAcrylate (MMA) and the resulting solid-state solutions have been pumped at 337 nm and 532 nm. Lasing efficiencies similar to those found in ethanol solution have been obtained with a 1:1 vol/vol HEMA: MMA copolymer matrix, and lifetimes of ca. 10 000 (337 nm pumping) and ca. 75 000 (532 nm pumping) pulses at repetition rates up to 15 Hz and 10 Hz, respectively, have been demonstrated.
A Costela - One of the best experts on this subject based on the ideXlab platform.
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photo physical characterization of Rhodamine 6G in a 2 hydroxyethyl methacrylate methyl methacrylate copolymer
Chemical Physics, 2000Co-Authors: W Holzer, Alfons Penzkofer, H Gratz, T Schmitt, A Costela, I Garciamoreno, R Sastre, F J DuarteAbstract:Abstract Some photo-physical parameters of 1×10−4 and 5.9×10−4 M samples of Rhodamine 6G in a 2-hydroxyethyl-methacrylate methyl-methacrylate copolymer (volume mixture 1:1) are determined and compared with Rhodamine 6G in methanol. They include the absorption cross-section and stimulated emission cross-section spectra, the fluorescence quantum distributions, quantum yields and lifetimes. The photo-degradation under steady-state and pulsed excitation is investigated. The saturable absorption behaviour under picosecond laser excitation is studied.
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internal photostabilization of polymeric solid state dye lasers based on trichromophoric Rhodamine 6G molecules
Chemical Physics Letters, 1997Co-Authors: A Costela, I Garciamoreno, F Amatguerri, He Tian, K Chen, M L Carrascoso, J Barroso, R SastreAbstract:Abstract We report on the lasing action of a modified Rhodamine 6G dye with two covalently bonded identical 1,8-naphthalimide groups in liquid solution in ethanol and in solid solutions in a methacrylate copolymer. When the solid samples are transversely pumped with 534 nm pulses at a repetition rate of 1 Hz, we have observed that the presence of the naphthalamide groups results in a clear photostabilization of the material. Possible mechanisms for the photostabilization process are suggested.
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solid state dye lasers based on modified Rhodamine 6G dyes copolymerized with methacrylic monomers
Journal of Applied Physics, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, Ricardo Mallavia, M D Santamaria, R SastreAbstract: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 N2 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 drop) 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.
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solid state dye lasers based on polymers incorporating covalently bonded modified Rhodamine 6G
Applied Physics Letters, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, R SastreAbstract:We report on the lasing action of modified Rhodamine 6G dyes copolymerized with methacrylic monomers. The laser samples were transversely pumped with a N2 laser at 337 nm. Lasing efficiencies similar to those found for Rhodamine 6G in ethanol solution have been achieved. Important increases in photostability, with lifetimes in excess of 20 000 shots at 2 Hz, have been obtained. By using a rotating mechanism, a stable output with no sign of degradation after half a million shots has been demonstrated.
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solid state dye lasers based on copolymers of 2 hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G
Applied Physics B, 1995Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, F Florido, R Duchowicz, R SastreAbstract:Rhodamine 6G has been dissolved in copolymers of 2-HydroxyEthyl MethAcrylate (HEMA) and Methyl MethAcrylate (MMA) and the resulting solid-state solutions have been pumped at 337 nm and 532 nm. Lasing efficiencies similar to those found in ethanol solution have been obtained with a 1:1 vol/vol HEMA: MMA copolymer matrix, and lifetimes of ca. 10 000 (337 nm pumping) and ca. 75 000 (532 nm pumping) pulses at repetition rates up to 15 Hz and 10 Hz, respectively, have been demonstrated.
F Amatguerri - One of the best experts on this subject based on the ideXlab platform.
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internal photostabilization of polymeric solid state dye lasers based on trichromophoric Rhodamine 6G molecules
Chemical Physics Letters, 1997Co-Authors: A Costela, I Garciamoreno, F Amatguerri, He Tian, K Chen, M L Carrascoso, J Barroso, R SastreAbstract:Abstract We report on the lasing action of a modified Rhodamine 6G dye with two covalently bonded identical 1,8-naphthalimide groups in liquid solution in ethanol and in solid solutions in a methacrylate copolymer. When the solid samples are transversely pumped with 534 nm pulses at a repetition rate of 1 Hz, we have observed that the presence of the naphthalamide groups results in a clear photostabilization of the material. Possible mechanisms for the photostabilization process are suggested.
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solid state dye lasers based on modified Rhodamine 6G dyes copolymerized with methacrylic monomers
Journal of Applied Physics, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, Ricardo Mallavia, M D Santamaria, R SastreAbstract: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 N2 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 drop) 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.
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solid state dye lasers based on polymers incorporating covalently bonded modified Rhodamine 6G
Applied Physics Letters, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, R SastreAbstract:We report on the lasing action of modified Rhodamine 6G dyes copolymerized with methacrylic monomers. The laser samples were transversely pumped with a N2 laser at 337 nm. Lasing efficiencies similar to those found for Rhodamine 6G in ethanol solution have been achieved. Important increases in photostability, with lifetimes in excess of 20 000 shots at 2 Hz, have been obtained. By using a rotating mechanism, a stable output with no sign of degradation after half a million shots has been demonstrated.
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solid state dye lasers based on copolymers of 2 hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G
Applied Physics B, 1995Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, F Florido, R Duchowicz, R SastreAbstract:Rhodamine 6G has been dissolved in copolymers of 2-HydroxyEthyl MethAcrylate (HEMA) and Methyl MethAcrylate (MMA) and the resulting solid-state solutions have been pumped at 337 nm and 532 nm. Lasing efficiencies similar to those found in ethanol solution have been obtained with a 1:1 vol/vol HEMA: MMA copolymer matrix, and lifetimes of ca. 10 000 (337 nm pumping) and ca. 75 000 (532 nm pumping) pulses at repetition rates up to 15 Hz and 10 Hz, respectively, have been demonstrated.
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laser action from Rhodamine 6G doped poly 2 hydroxyethyl methacrylate matrices with different crosslinking degrees
Chemical Physics Letters, 1993Co-Authors: F Amatguerri, A Costela, J M Figuera, F Florido, R SastreAbstract:Abstract The lasing properties of Rhodamine 6G dissolved in poly (2-hydroxyethyl methacrylate) matrices with different amounts of ethylene glycol dimethacrylate as crosslinking monomer are investigated. Increasing the rigidity of the matrix by decreasing the polymer free volume results in significant increases of both lasing efficiency and photostability. There exists an optimum degree of crosslinking for which efficiency and photostability reach the highest values.
George C Schatz - One of the best experts on this subject based on the ideXlab platform.
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surface enhanced raman excitation spectroscopy of a single Rhodamine 6G molecule
Journal of the American Chemical Society, 2009Co-Authors: Jon A Dieringer, George C Schatz, Jon P Camden, Kristin L Wustholz, David J Masiello, Samuel L Kleinman, Richard P Van DuyneAbstract:The surface-enhanced Raman excitation profiles (REPs) of Rhodamine 6G (R6G) on Ag surfaces are studied using a tunable optical parametric oscillator excitation source and versatile detection scheme. These experiments afford the ability to finely tune the excitation wavelength near the molecular resonance of R6G (i.e., approximately 500-575 nm) and perform wavelength-scanned surface-enhanced Raman excitation measurements of a single molecule. The ensemble-averaged surface-enhanced REPs are measured for collections of molecules on Ag island films. The relative contributions of the 0-0 and 0-1 vibronic transitions to the surface-enhanced REPs vary with vibrational frequency. These results highlight the role of excitation energy in determining the resonance Raman intensities for R6G on surface-enhancing nanostructures. Single-molecule measurements are obtained from individual molecules of R6G on Ag colloidal aggregates, where single-molecule junctions are located using the isotope-edited approach. Overall, single-molecule surface-enhanced REPs are narrow in comparison to the ensemble-averaged excitation profiles due to a reduction in inhomogeneous broadening. This work describes the first Raman excitation spectroscopy studies of a single molecule, revealing new information previously obscured by the ensemble.
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surface enhanced raman excitation spectroscopy of a single Rhodamine 6G molecule
Journal of the American Chemical Society, 2009Co-Authors: Jon A Dieringer, George C Schatz, Jon P Camden, Kristin L Wustholz, David J Masiello, Samuel L Kleinman, Richard P Van DuyneAbstract:The surface-enhanced Raman excitation profiles (REPs) of Rhodamine 6G (R6G) on Ag surfaces are studied using a tunable optical parametric oscillator excitation source and versatile detection scheme. These experiments afford the ability to finely tune the excitation wavelength near the molecular resonance of R6G (i.e., ∼500−575 nm) and perform wavelength-scanned surface-enhanced Raman excitation measurements of a single molecule. The ensemble-averaged surface-enhanced REPs are measured for collections of molecules on Ag island films. The relative contributions of the 0−0 and 0−1 vibronic transitions to the surface-enhanced REPs vary with vibrational frequency. These results highlight the role of excitation energy in determining the resonance Raman intensities for R6G on surface-enhancing nanostructures. Single-molecule measurements are obtained from individual molecules of R6G on Ag colloidal aggregates, where single-molecule junctions are located using the isotope-edited approach. Overall, single-molecule...
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interaction of plasmon and molecular resonances for Rhodamine 6G adsorbed on silver nanoparticles
Journal of the American Chemical Society, 2007Co-Authors: J. Zhao, Jiha Sung, Lasse Jensen, Shengli Zou, George C SchatzAbstract:Localized surface plasmon resonance (LSPR) is a key optical property of metallic nanoparticles. The peak position of the LSPR for noble-metal nanoparticles is highly dependent upon the refractive index of the surrounding media and has therefore been used for chemical and biological sensing. In this work, we explore the influence of resonant adsorbates on the LSPR of bare Ag nanoparticles (λmax,bare). Specifically, we study the effect of Rhodamine 6G (R6G) adsorption on the nanoparticle plasmon resonance because of its importance in single-molecule surface-enhanced Raman spectroscopy (SMSERS). Understanding the coupling between the R6G molecular resonances and the nanoparticle plasmon resonances will provide further insights into the role of LSPR and molecular resonance in SMSERS. By tuning λmax,bare through the visible wavelength region, the wavelength-dependent LSPR response of the Ag nanoparticles to R6G binding was monitored. Furthermore, the electronic transitions of R6G on Ag surface were studied by ...
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resonance raman scattering of Rhodamine 6G as calculated using time dependent density functional theory
Journal of Physical Chemistry A, 2006Co-Authors: Lasse Jensen, George C SchatzAbstract:In this work, we present the first calculation of the resonance Raman scattering (RRS) spectrum of Rhodamine 6G (R6G) which is a prototype molecule in surface-enhanced Raman scattering (SERS). The calculation is done using a recently developed time-dependent density functional theory (TDDFT) method, which uses a short-time approximation to evaluate the Raman scattering cross section. The normal Raman spectrum calculated with this method is in good agreement with experimental results. The calculated RRS spectrum shows qualitative agreement with SERS results at a wavelength that corresponds to excitation of the S1 state, but there are significant differences with the measured RRS spectrum at wavelengths that correspond to excitation of the vibronic sideband of S1. Although the agreement with the experiments is not perfect, the results provide insight into the RRS spectrum of R6G at wavelengths close to the absorption maximum where experiments are hindered due to strong fluorescence. The calculated resonance...
I Garciamoreno - One of the best experts on this subject based on the ideXlab platform.
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photo physical characterization of Rhodamine 6G in a 2 hydroxyethyl methacrylate methyl methacrylate copolymer
Chemical Physics, 2000Co-Authors: W Holzer, Alfons Penzkofer, H Gratz, T Schmitt, A Costela, I Garciamoreno, R Sastre, F J DuarteAbstract:Abstract Some photo-physical parameters of 1×10−4 and 5.9×10−4 M samples of Rhodamine 6G in a 2-hydroxyethyl-methacrylate methyl-methacrylate copolymer (volume mixture 1:1) are determined and compared with Rhodamine 6G in methanol. They include the absorption cross-section and stimulated emission cross-section spectra, the fluorescence quantum distributions, quantum yields and lifetimes. The photo-degradation under steady-state and pulsed excitation is investigated. The saturable absorption behaviour under picosecond laser excitation is studied.
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internal photostabilization of polymeric solid state dye lasers based on trichromophoric Rhodamine 6G molecules
Chemical Physics Letters, 1997Co-Authors: A Costela, I Garciamoreno, F Amatguerri, He Tian, K Chen, M L Carrascoso, J Barroso, R SastreAbstract:Abstract We report on the lasing action of a modified Rhodamine 6G dye with two covalently bonded identical 1,8-naphthalimide groups in liquid solution in ethanol and in solid solutions in a methacrylate copolymer. When the solid samples are transversely pumped with 534 nm pulses at a repetition rate of 1 Hz, we have observed that the presence of the naphthalamide groups results in a clear photostabilization of the material. Possible mechanisms for the photostabilization process are suggested.
-
solid state dye lasers based on modified Rhodamine 6G dyes copolymerized with methacrylic monomers
Journal of Applied Physics, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, Ricardo Mallavia, M D Santamaria, R SastreAbstract: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 N2 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 drop) 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.
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solid state dye lasers based on polymers incorporating covalently bonded modified Rhodamine 6G
Applied Physics Letters, 1996Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, R SastreAbstract:We report on the lasing action of modified Rhodamine 6G dyes copolymerized with methacrylic monomers. The laser samples were transversely pumped with a N2 laser at 337 nm. Lasing efficiencies similar to those found for Rhodamine 6G in ethanol solution have been achieved. Important increases in photostability, with lifetimes in excess of 20 000 shots at 2 Hz, have been obtained. By using a rotating mechanism, a stable output with no sign of degradation after half a million shots has been demonstrated.
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solid state dye lasers based on copolymers of 2 hydroxyethyl methacrylate and methyl methacrylate doped with Rhodamine 6G
Applied Physics B, 1995Co-Authors: A Costela, I Garciamoreno, J M Figuera, F Amatguerri, F Florido, R Duchowicz, R SastreAbstract:Rhodamine 6G has been dissolved in copolymers of 2-HydroxyEthyl MethAcrylate (HEMA) and Methyl MethAcrylate (MMA) and the resulting solid-state solutions have been pumped at 337 nm and 532 nm. Lasing efficiencies similar to those found in ethanol solution have been obtained with a 1:1 vol/vol HEMA: MMA copolymer matrix, and lifetimes of ca. 10 000 (337 nm pumping) and ca. 75 000 (532 nm pumping) pulses at repetition rates up to 15 Hz and 10 Hz, respectively, have been demonstrated.