▎ 摘　　要

A stable passive Q-switched Erbium doped fiber laser (EDFL) operating at 1533 nm is demonstrated using a multi-layer graphene oxide (GO) based saturable absorber. The GO was synthesized via chemical oxidation of graphite flakes at room temperature using a simplified Hummer's method. By dipping a fiber ferrule end face onto the GO suspension, GO is successfully coated onto the end face, making it a simple saturable absorption device. At 980 nm pump power of 40 mW, the EDFL generates an optical pulse train with a repetition rate of 12.98 kHz and pulse width of 13 mu s. The highest energy of 0.46 mu J is achieved at the maximum pump power of 90 mW. The pulse width ranges from 5.14 to 14.63 mu s.