A characterization of Rhodamine 640 for optical amplification: Collinear pump and signal gain properties in solutions, thin-film polymer dispersions, and waveguides

Abstract

We report a study of the optical signal amplification properties of Rhodamine 640 in solution, in thin-film format dispersed within a poly(methyl methacrylate) (PMMA) polymer matrix, and in a waveguiding structure created by coating polymer-dispersed Rhodamine 640 onto a patterned quartz substrate. The optical signal amplification experiments were carried out using a collinear pump and signal setup. Depending on both pump and signal energies, gains of up to 41 dB were achieved in solution, while 1% by weight dye-doped PMMA films showed net gains of 54cm−1, and associated losses of 16cm−1. Using the same concentration dye/PMMA dispersions, waveguide structures were fabricated with a 120×1μm2 cross section and a length of 1.2 cm. The internal optical gain values measured at 625 and 650 nm were found to be as high as 26 and 8 dB, respectively. The corresponding signal-to-noise ratio was in the 7–21-dB range at 625 nm and in the 3–21-dB range at 650 nm. Both in solution and in the waveguide structures we found that amplified spontaneous emission had a detrimental effect on the optical gain characteristics through a decrease in the signal-to-noise ratio.

Laser turn-on behavior in organic vertical-external cavity surface-emitting lasers

“…A complete description of the setup and useful description of laser physics in VECSOLs can be found in [20]. In the following, equations from section 2 are used for theoretical calculation of the VECSOL output energy when the pump pulse duration is varied in a continuous manner from 0.1 to 4 ns.…”

Compact optical amplifier with large core fabricated by doping with vaporized functional dye

“…To determine the wavelength of the most effective excitation, it is necessary to measure the excitation spectrum of the amplifier. There have been many reports of determination of pumping wavelength from the absorption maximum [4][5][6]13]. However, the absorption maximum cannot always be suitable for the excitation to emit fluorescence.…”

“…large core size and long fibre length. On the other hand, waveguide amplifiers are compact but have small cores causing difficulty in alignment of POFs [6]. Therefore, there is a need for waveguide amplifiers with large cores.…”

Amplification Characteristics of a Coumarin 460-Based Tunable Amplifier

“…Lam and Damzen [11] studied pyrromethene 650 as a material with potential applications in optical amplification. In a 7-mm-long polymethylmethacrylate (PMMA) sample, they achieved gains of 26 dB using a dye concentration of 120 ppm in PMMA and M. C. Ramon et al [12] achieved a gain of 41 dB in solution using rhodamine 640. Additionally, the internal optical gain values measured at 625 and 650 nm were found to be 26 and 8 dB with dye and PMMA dispersions, respectively.…”