Titanium Selenide Saturable Absorber Mirror for Passive Q-Switched Er-Doped Fiber Laser

Titanium selenide saturable absorber mirror (TiSe
₂
-SAM) is fabricated by a combination of magnetron sputtering method and chemical vapor deposition method. With the optical circulator, the TiSe
₂
-SAM is flexibly injected in the experimental cavity as the saturated absorber, and a steady Q-switched Er-doped fiber (EDF) laser is established. The modulation depth of TiSe
₂
-SAM is measured to be 25.92%. Through appropriately adjusting the polarization states and changing the pump power, the shortest pulse duration and maximum output power of the passive Q-switched EDF laser are 1.126 μs and 11.54 mW, respectively. The adjustable range of the repetition rate is 70-154 kHz, and the signal to noise ratio is greater than 62 dB. To our best knowledge, there is no report on Q-switched EDF lasers based on TiSe
₂
up to now, and our new attempt on TiSe
₂
-based Q-switched EDF laser proves that TiSe
₂
as a powerful candidate is promising in ultrafast optical generation for the characteristics of high modulation depth and high stability.