We report two-wavelength pump-probe measurements of the metastable state lifetime in a high-concentration erbium-doped fiber (EDF). The lifetimes under population inversion conditions are measured using a 980 nm pump laser and a 1.5 µm probe laser. The lifetime variation from the lifetime under low excitation conditions to that of a highly inverted population are calculated using a model derived from the rate equations. To confirm the validity of our method, we compare the results obtained with those for temporally resolved spontaneous emissions in the perpendicular direction and those measured using a 1.5 µm single-wavelength pump–probe technique in our previous work.

中文翻译：

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在 980 nm 泵浦和 1.5 µm 探测波长下，在粒子数反转条件下测定高浓度掺铒光纤的亚稳态寿命

我们报告了高浓度掺铒光纤 (EDF) 中亚稳态寿命的双波长泵浦探针测量。使用 980 nm 泵浦激光器和 1.5 µm 探针激光器测量粒子数反转条件下的寿命。使用从速率方程导出的模型计算从低激发条件下的寿命到高度倒置的种群寿命的寿命变化。为了确认我们方法的有效性，我们将获得的结果与垂直方向上的时间分辨自发发射的结果以及在我们之前的工作中使用 1.5 µm 单波长泵浦探针技术测量的结果进行比较。