Flat broadband erbium-doped fiber ASE source based on symmetric nonlinear optical loop mirror

A new type of flat broadband Erbium-doped fiber (EDF) amplified spontaneous emission source is proposed and demonstrated. The intensity-dependent loss induced by a symmetric nonlinear optical loop mirror is used to flatten the spectrum and broaden the bandwidth. The 3 dB bandwidth over 50 nm has been obtained with 15 m EDF and 100 mW pump power based on the single-pass forward pump configuration. This spectrum flattening and broadening method is quite effective over a large range both in pump power and EDF length.

https://link.springer.com/article/10.1134%2FS1054660X10150223