A 1550nm PbSe quantum dots fiber amplifier excited by evanescent wave

A novel quantum dots(QDs) optical fiber amplifier was proposed and demonstrated. It was fabricated by dip-coating the PbSe quantum dots doped sol onto the taper region of fiber coupler. The PbSe quantum dots was synthesized according to a colloidal method. And a lower refractive index sol was also synthesized as the host of PbSe QDs. A standard single mode fiber was used to make the fusion tapered fiber coupler which had double input and output ports. With the simple structure, a signal and a pump can be injected into the amplifier and excite the PbSe QDs through evanescent wave. As shown in the experimental results, the amplified light wave was observed at 1550nm wavelength with 980nm wavelength LD as pump.