Graded index polymer optical fiber amplifiers

Gain dynamics such as signal wavelength dependence and pump wavelength dependence for organic dye-doped graded index (GI) polymer optical fiber amplifiers (POFA) are characterized. A Rhodamine B-doped POFA, 1 m in length and 0.3 mm in core diameter, has exhibited more than 20 dB gain at signal wavelengths from 560 nm to 600 nm when optically pumped at 532 nm. The maximum gain of 37 dB was achieved with a Rhodamine B-doped POFA pumped at 550 nm, which was optimum pump wavelength. For an Oxazine 4-doped POFA, signal gain of 20 dB was obtained when pumped at 605 nm. It is shown that pumping at absorption maximum wavelengths optimizes amplifier performance.