Generation of Passive Q-switched by using Graphene Oxide in Erbium Doped Fiber Laser

The past decade has seen the rapid development of saturable absorber in various material and structure. Graphene is known as one of the best materials used as the saturable absorber for optical fiber laser due to its flat honeycomb shape. However, graphene is costly and relatively challenging to produce. Therefore, the alternative was used to solve this issue by oxidize it to form graphene oxide. This research is based on graphene oxide saturable absorber. Incorporating small portion of the graphene oxide based polyvinyl alcohol into a cavity of Erbium-doped fiber laser, generate a stable Q-switched pulsed that operate in a wavelength of 1560.50 nm within an adjustable pump power range of 16.88mW to 72.85mW. The increasing of the pump power, causes the repetition rate to be increased from 32.45kHz to 81.7kHz with the shortest pulse width of 5.67 us. Other than that, this Q-switched has a high output power and high pulse energy of 8.93mW and 109.30 nJ. These prove that graphene oxide consists of flexibility and easy to be sandwich in the laser cavity. However, graphene oxide still has a room for improvement to offers a better Q-switched fiber laser.