| 초록 |
The amplification gain of current EDFA based on erbium (Er(III))-doped silica materials is not enough for amplifying the optical signals in small-sized photonic devices, while the amplification gain is not a problem for long distance of several to tens of meters. To get high gain of 30dB in small-sized photonic devices, one solution may be to design the spiral-typed planar waveguide for making a device with long pathway. However, problems in design and fabrication of spiral-typed planar waveguides with small radius and high curvature-related loss make it difficult to produce miniature sized and more variety of photonic devices. In addition, Er(III)-doped concentration on silica optic fiber is limited to 100-1000 ppm. If higher than the limiting concentration is to be employed, Er(III) ion interaction between themselves would cause non-radiative process to occur, hence rapidly reducing the amplification gain. For these reasons, it is not possible to obtain the amplification gain of higher than 30dB with Er(III)-doped silica optical fibers for developing integrated planar waveguide amplifiers (IPWAs). In order to solve above mentioned problems and realize the development of IPWAs, we have developed novel erbium-cored integrated supramolecular systems with highly efficient light-harvesting dendritic arrays for optical amplification. Er(III) ions were encapsulated by supramolecular ligands such as porphyrins, macrobicyclics, carcerand, bispherand, and cavitacryptands, etc. The supramolecular ligands were specially designed and synthesized in order to provide enough coordination sites to form stable Er(III)-chelated complexes. For getting a higher optical amplification gain, also, their energy levels were tuned to maintain the effective energy transfer process from supramolecular ligands to erbium(III) ions. Furthetmore, to maximize the light-harvesting effect, we have incorporated new aryl ether-typed dendrons as photon antennas into integrated supramolecular systems. In this presentation, synthesis and luminescence properties of novel erbium-cored integrated supramolecular systems with highly efficient light-harvesting dendritic arrays for integrated planar waveguide amplifiers will be overviewed. |
