Self-written active waveguide for integrated optical amplifiers

The authors propose a fabrication method of optical amplifying devices, which is based on a technique of light-induced self-written waveguide. The waveguide structure doped with infrared organic dye molecules was self-written by visible laser light irradiation from optical fiber tips to photopolymerized resin, which makes the waveguide self-aligned with input and output fibers. The self-written “active” waveguides with the length of $0.98–1.89\mathrm{mm}$ were fabricated and amplified spontaneous emission at $\sim 790\mathrm{nm}$ was observed. Furthermore, optical amplification of externally input light was also implied in a tentative examination.