Pulse broadening in long-span dispersion-free single-mode fibres at 1.5 ¿m

Dispersion-free single-mode fibres at 1.5 ¿m were fabricated by controlling their waveguide dispersion and dopant-dependent material dispersion. Pulse broadening in the 20 km long fibre was measured by using a laser diode operated at 1.5 ¿m. Measured pulse broadening was 1.3 ps/km nm, which is in good agreement with theoretical results. The present experiment confirms that it is beneficial to use such fibres for large-capacity and long-distance transmission media.