Characteristics of time-gated raman amplification in GaP-AlGaP semiconductor waveguides
Characteristics of time-gated raman amplification in GaP-AlGaP semiconductor waveguides
复制标题
GaP-AlGaP半导体波导的时间选通拉曼放大特性
DOI：
10.1063/1.1513870
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发表时间：
2003
影响因子：
3.2
通讯作者：
J. Nishizawa
中科院分区：
文献类型：
--
作者：
T. Tanabe;K. Suto;Tatsuya Saito;T. Kimura;Y. Oyama;J. Nishizawa
采用80ps脉冲宽度的锁模钛蓝宝石泵浦源研究了GaP-AlGaP波导中的时间门控拉曼放大。当增益小于10 dB时，对数拉曼增益随泵浦功率密度的增加而线性增加。然而，随着泵功率的进一步增加，它几乎与泵功率密度的平方根成正比。这是因为泵浦脉冲的等效线宽与拉曼增益系数（24 GHz）的光谱全宽最大值的一半相当。另一点是，由于拉曼放大的发生主要是由于后向散射，当波导长度超过泵浦光宽对应的光长时，被放大的脉冲变宽。
Time-gated Raman amplification in the GaP–AlGaP waveguide is investigated using mode-locked Ti–sapphire pump source with 80 ps pulse width. Logarithmic Raman gain linearly increases with increasing the pump power density as long as the gain is less than about 10 dB. However, with further increasing the pump power it becomes nearly proportional to the square root of the pump power density. This is due to the fact that the equivalent linewidth of the pump pulse is comparable to the spectral full width half maximum of the Raman gain coefficient (24 GHz). Another point is that the amplified pulse broadens as the waveguide length exceeds the optical length corresponding to the pump pulse width because Raman amplification occurs mainly due to backward scattering.