Intervalley scattering in GaAs–AlAs quantum cascade lasers
Intervalley scattering in GaAs–AlAs quantum cascade lasers
复制标题
GaAs-AlAs 量子级联激光器中的谷间散射
DOI：
10.1063/1.1500775
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发表时间：
2002
影响因子：
4
通讯作者：
R. Airey
中科院分区：
文献类型：
--
作者：
L. Wilson;D. Carder;J. Cockburn;R. Green;D. Revin;M. Steer;M. Hopkinson;G. Hill;R. Airey
研究了具有间接带隙AlAs势垒的Γ-Χ基量子级联激光器中Γ点量子势垒态与X点势垒态之间谷间电子转移的重要性。研究了一系列样品，其中耦合的注入器/上激光能级与注入势垒中最低限制的X能级之间的能量间隔是不同的。我们证明了要发生激光，电子注入到上激光能级必须通过限制在注入势垒中最低X态以下的Γ态进行。这对当前激光器设计的最小工作波长(λ≈8 μm)施加的限制通过利用双注入势垒来实现λ=7.2 μm的激光来克服。
We have investigated the importance of intervalley (Γ–Χ) electron transfer between Γ-point quantum well states and X-point barrier states in GaAs-based quantum cascade lasers with indirect band gap AlAs barriers. A series of samples has been studied in which the energy separation between the coupled injector/upper laser levels and the lowest confined X state in the injection barrier is varied. We demonstrate that for lasing to occur, electron injection into the upper laser level must proceed via Γ states confined below the lowest X state in the injection barrier. The limit this places on the minimum operating wavelength (λ≈8 μm) for the present laser design is overcome by utilizing a double injection barrier to achieve lasing at λ=7.2 μm.