Erbium-doped fiber amplifier with flattened gain spectrum

Abstract

An optical notch filter was incorporated within the length of all erbium-doped fiber amplifier. Careful choice of the filter characteristics and location made it possible to enhance the amplifier gain at wavelengths around 1550 nm. An amplifier with 27-dB gain and 33-nm bandwidth was demonstrated. The saturation characteristics of the amplifier were uniform across its gain spectrum, making it ideal for wavelength division multiplexed (WDM) application.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>