Q-switched Zr-EDF laser using single-walled CNT/PEO polymer composite as a saturable absorber

In this work, we propose and demonstrate a compact, Zirconia–Erbium Doped Fiber (Zr-EDF), a new type of fiber with zirconia dopants added to the silica glass host to significantly increase erbium ion concentrations in the glass matrix. Q-switched behavior is obtained by using a Single-Walled Carbon Nanotube/Polyethylene Oxide composite sandwiched between two fiber ferrules as a saturable absorber. The Zr-EDF fiber laser has a nearly flat amplified spontaneous emission spectrum from 1545 to 1565 nm, unlike conventional erbium doped fibers. The pulse train generated has a maximum repetition rate and pulse width of 14.20 kHz and 8.6 μs respectively. The highest average output power of the system is 270.0 μW, with a corresponding pulse energy of 19.02 nJ. The proposed system is compact, cost-effective and rugged and has applications in range-finding, medicine and in industry.

► A new fiber with Zr dopants for very high Er ion concentrations in short fibers.
► Zr-EDF has a nearly flat ASE spectrum from 1545 to 1565 nm.
► Single-Walled Carbon Nanotube/Polyethylene Oxide composite as a saturable absorber.
► Generation of Q-switched pulses in Zr-EDF laser using SWCNT/PEO SA.
► Generated pulse train with repetition rate of 14.20 kHz and pulse width of 8.6 μs.