Er-doped Laser Amplifer(EFA)

When EFA developed by Erbium group amplifies the seed laser power, the increase of the frequency and intensity noise is kept in extreme low range. The linewidth is less than 10 Hz, and the intensity noise (RIN) is less than -140 dBc/ HZ@ 100 kHz. Compared to the scheme of directly power-amplified 780 nm diode laser, the scheme of utilizing Er-doped fiber amplifier (EFA) as 1560 nm laser amplifier adopted by Erbium group can get higher power. The maximum laser power outputted with stable and long lifetime by EFA can be up to 15 W. Due to all fiber structure, the EFA have excellent environmental stability.

Low noise fiber amplifier and seed laser relative line width broadening and its measurement method