Carboxyl graphene oxide solution saturable absorber for femtosecond mode-locked erbium-doped fiber laser

Lv Rui-dong¹, Li Lu², Wang Yong-gang^{1, †}, Chen Zhen-dong¹, Liu Si-cong¹, Wang Xi³, Wang Jiang¹, Li Yong-fang¹

(color online) (a) Relationship between the pump power and output power. (b) Long term optical spectrum measured over 60 h.