High pumping-efficiency L-band erbium-doped fiber ASE source using doublepass bidirectional-pumping configuration

We present a high pumping-efficiency L-band (1565~1605 nm) erbium-doped fiber amplified spontaneous-emission (ASE) source using a double-pass bidirectional pumping configuration. Such design gives rise to relaxing the danger in resonant lasing, allowing high pumping-power operation, and therefore, enhancing the pumpingconversion efficiency. The ASE source has a mean wavelength of 1584.3 nm, a spectral linewidth of 41.6 nm, and an output power of 71.8 mW with a ripple of 0.5 dB without using any external spectral filters. The high pumping efficiency of 42.2% is achieved.