Summary: Steady-state Amplifiers and Lasers in a Solid Polymer
J. Yang, C. Grivas, F. Ay, M.B.J. Diemeer, A. Driessen, and M. Pollnau
Incorporation of rare-earth ions into polymers is challenging due to the immiscibility of their salt
precursors with organic solvents. This problem can be overcome by encapsulating the ions with
organic ligands to form stable complexes that can be easily dispersed in polymer solutions.
Furthermore, the ligands can shield the dopant ion from impurities in the surrounding matrix that
otherwise would quench the luminescence . By optimizing the fabrication procedure of both, host
material and optical waveguide structure, we have succeeded in demonstrating optical net gain and
the first continuous-wave (cw) laser emission in a solid polymer. The lasers operate near 1060 nm
and 873 nm, providing up to 0.98 mW of output power.
1. A Polymer for Rare-earth-ion Doping
A polymer host material, based on a cycloaliphatic diepoxy cured with a fluorinated dianhydride, has
been developed. When activated with the rare-earth-ion-doped complex,
neodymium(thenoyltrifluoroacetone)3 1,10-phenanthroline (Fig. 1, left), the typical absorption and
emission lines of the Nd3+
ion were detected. Luminescence quenching, which usually occurs in
polymers due to high-energy vibrations from OH and CH chemical bonds, was eliminated by the
neutral 1,10-phenanthroline ligand and by applying fluorinated chelates to the complex, respectively,
and absorption due to the polymer host occurs only in the wavelength range longer than 1100 nm.
The functionalities of active doping and photo-definition were divided over two different