Abstract—We demonstrate an ultrafast TDFL Q-switched pulse in 2 μm wavelength using multi-walled carbon nanotubes (MWCNTs) as passive saturable absorber (SA). MWCNTs film is sandwiched between two fibre connectors or patch cords after deposited with index matching gel on the fibre ferrules. Thulium-doped fibre was pumped using 1552 nm source in the ring cavity. The repetition rate for the pulses can be tuned from 13.33 kHz to 21.07 kHz by varying the pump power from 307.5 mW to 371.4 mW. At the maximum power, the pulse generated energy of 87.34 nJ with full-width at half maximum (FHWM) of 8.21 μs.

Index Terms—Multi-walled carbon nanotubes, passive saturabe absorber, Q-switching.

M. T. Ahmad, A. A. Latiff, and Z. Zakaria are with the Faculty of Electronic and Computer Engineering, Universiti Teknikal Malaysia Melaka, 76100 Melaka, Malaysia (e-mail: taufiq5015@ gmail.com).
S. W. Harun is with the Photonic Research Centre, Universiti of Malaya, 50603 Kuala Lumpur, Malaysia (e-mail: swharun@um.edu.my).

Cite:M. T. Ahmad, A. A. Latiff, Z. Zakaria, and S. W. Harun, "Q-Switched Ultrafast TDFL Using MWCNTs-SA at 2 µm Region," International Journal of Computer and Communication Engineering vol. 3, no. 6, pp. 446-449, 2014.