▎ 摘　　要

We demonstrate a tunable wavelength Q-switched erbium doped fiber laser (EDFL) using a graphene oxide (GO) saturable absorber (SA). The GO solution was prepared using the simplified Hummer's method, which is then thinly spread into a petri-disk to make a paper-like material. The GO paper is sandwiched between two FC/PC fiber connectors and incorporated into a ring EDFL's cavity for Q-switching operation. The wavelength tunable operation of the Q-switched laser was obtained with a band-pass filter. The stable Q-switched pulse with a tunable range from 1536 nm to 1563 nm was achieved, covering a wavelength range over similar to 28 nm. The Q-switched EDFL produced maximum pulse energy of 151 nJ at pump power of 80 mW.