Thulium Fiber Laser is a laser doped Thulium as gain media. Thulium doped gain media are laser gain media doped with erbium ions.

The thulium fiber in thulium fiber laser allows for pulse prolongation up to 12 ms. Pulses are regular. The power produced by the thulium fiber laser has a constant peak, called the super pulse creation. This effect of pulsation is stable over time.