Experimental configuration of a ring laser cavity that includes quarter-waveplates (QWP), passive polarizer, half-waveplate (HWP), ytterbium-doped amplification, and output coupler. The Yb-doped section of the fiber is fused with standard single-mode fiber and treated in a distributed fashion. The angles , , , and of the discrete mode-locking elements can all be measured with reasonable accuracy. The dotted lines denote free space (from [6]).
