实用的L波段EDFA(掺铒光纤放大器)常采用多段铒纤和多泵浦的复杂结构。对一种复杂结构的L波段EDFA的温度特性进行了实验研究，发现在不同的输入光功率下，L波段短波侧(约1 570～1 582 nm)的增益谱可按相反的方式随温度而变化，并从理论上解释了此现象。实验结果表明，铒纤的温度和增益斜率之间仍然存在很好的线性关系。控制铒纤温度就可以调整L波段EDFA的增益斜率，获得平坦的增益。

Practical L-band Erbium-Doped Fiber Amplifiers (EDFA) often adopt multi-stage Erbium-doped fiber and multi-pump lasers. In this paper, the temperature characteristic of an L-band EDFA with such a complex configuration is experimentally investigated. It is found that the gain spectra of the short-wavelength (about 1 570~1 582 nm) side of the L-band change with temperature in a reverse direction, which is theoretically explained. The experimental results show that there is still a good linear relationship between the Er-doped fiber temperature and the L-band EDFA gain tilt. Thus, the gain tilt of L-band EDFA can be adjusted by controlling the fiber temperature so as to achieve flattened gain.