Frequency doubling of 1549 nm, 3 ns pulse using all-fibre system

Periodically poled D-shape standard singlemode fibres were used to generate second harmonics of 1549 nm, 3 ns pulses generated by an all-fibre system, where pump pulses, seeded by an external cavity tunable LD and amplified by a chain of EDFAs, were launched into the poled fibre by a butt-joint. The authors believe that the present nonlinear test of D-shape standard singlemode fibres using the all-fibre system exploits the prospect of fibre devices in a fibre network system.