Ultrashort pulse generation in erbium-doped fiber lasers in South America: a historical review

This paper reviews the scientific contributions of the last 30 years on erbium-doped fiber laser ultrashort pulse generation in South America. The focus is on contributions authored in South American institutions. It reveals a wide variety of laser cavities, ranging in length from a few centimeters to tens of kilometers, and optical pulses, from tens of femtoseconds to nanoseconds, with fully controlled average and peak powers. Furthermore, different approaches for ultrashort pulse generation using active (synchronous and asynchronous) and/or passive mode-locking techniques are discussed, as well as the employment of nonlinear optical phenomena (Kerr effect) and several two-dimensional nanomaterials as saturable absorbers, such as carbon nanotubes, graphene, graphite, graphene oxide, reduced-graphene oxide, semiconductor transition metal dichalcogenides, and black phosphorus. Finally, the paper revisits and discusses several advances, important milestones, and records on ultrashort pulse generation in erbium-doped fiber lasers, with many essential outcomes attesting to the high quality of research carried out in South America in the field of ultrafast fiber lasers.