Gain-clamping erbium-doped waveguide amplifier module using optical feedback technique

A forward optical feedback technique for gain-clamping erbium-doped waveguide amplifier has been proposed and experimentally investigated. Three different saturated tones are selected in this proposed structure over the operation range from 1530 to 1550 nm to realize the amplification behaviors. Therefore, a dynamic range of input signal power from −9 to −40 dBm at 1552 nm is obtained when different power level and lasing position of the saturated tone are applied. In addition, the gain clamping performance has also been investigated experimentally under different operation conditions such as the lasing wavelength, the cavity loss and the input signal wavelength.