Direct measurement of carbon nanotube temperature between fiber ferrules as a universal tool for saturable absorber stability investigation

Single-walled carbon nanotubes (SWCNTs) are widely explored for the ultrashort pulse generation in fiber lasers enabled by pronounced saturable absorption (SA) effect. Despite many remarkable results demonstrated area, degradation of samples inside laser cavity limits widespread use SWCNT-SA. In present work, we investigate mechanism measuring temperature an operating accordance with Raman G-band position. We identify process behind sample comparing burning thermogravimetric analysis. apply this approach SWCNTs polyvinyl alcohol polymer matrix and polymer-free SWCNT thin film demonstrate that these undergo different mechanism. Proposed technique provides a useful instrument optimization SWCNT-SA desired ultrafast generation.