Passively Q-switched erbium-doped fiber laser at L-band region by employing multi-walled carbon nanotubes as saturable absorber

摘要

AninexpensiveandsimplepassivelyQ-switchedErbium-dopedfiberlaser(EDFL)operatingintheL-bandregionwithastablepulsetrainisgeneratedbyemployingamulti-walledcarbonnanotubes(MWCNTs)polymercompositefilmbasedsaturableabsorber.ByincorporatingtheSAwitha50mErbiumdopedfiber(EDF)inalasercavity,Q-switchedpulsegenerationintheL-bandregionismadepossible.nbsp;Therepetitionrateofthepulsetrainrangesfrom12.3kHzto14.4kHzasthe1480nmpumppowerisvariedfrom89.4mWto106.1mW.Atthehighestpumppowerof106.1mW,thepulsewidthandpulseenergyofthelaserare10.8micro;sand135.1nJ,correspondingly.Thesaturableabsorber(SA)isconstructedfromatinypieceofMWCNTsthinfilmsandwichedbetweentwoFC/PCfiberconnectors.ThefilmispreparedbymixingMWCNTshomogeneoussolutionwithadilutedPolyvinylalcohol(PVA)polymersolutionandlefttodryatroomtemperature.