Flexible all-PM NALM Yb:fiber laser design for frequency comb applications: operation regimes and their noise properties
Mayer, Aline S., Grosinger, Wilfrid, Heckl, Oliver H., Fellinger, Jakob, Winkler, Georg, Perner, Lukas W., Droste, Stefan, Salman, Sarper H., Li, Chen, Heyl, Christoph M., Hartl, Ingmar
Abstract
We present a flexible all-polarization-maintaining (PM) mode-locked ytterbium(Yb):fiber laser based on a nonlinear amplifying loop mirror (NALM). In addition to providingdetailed design considerations, we discuss the different operation regimes accessible by thisversatile laser architecture and experimentally analyze five representative mode-locking states.These five states were obtained in a 78-MHz configuration at different intracavity group delaydispersion (GDD) values ranging from anomalous (-0.035 ps$^2$) to normal (+0.015 ps$^2$). We put aparticular focus on the characterization of the intensity noise as well as the free-running linewidthof the carrier-envelope-offset (CEO) frequency as a function of the different operation regimes.We observe that operation points far from the spontaneous emission peak of Yb (∼1030 nm) andclose to zero intracavity dispersion can be found, where the influence of pump noise is stronglysuppressed. For such an operation point, we show that a CEO linewidth of less than 10-kHz at1 s integration can be obtained without any active stabilization