A GaSb/GaAsBi type-II quantum dot structure is proposed for fabricating middle-wave infrared (MWIR) and long-wave infrared (LWIR) lasers. The finite element method is employed to investigate the train distributions and band structures of the proposed structures with different Bi contents and QD sizes. It is found that the strain component ε_xx decreases with Bi contents and heights, and increases with the diameter, while the component ε_zz inversely changes. The charge carriers recombine between the electrons in GaAsBi QDs and the holes in GaSb. The energy of the ground states of electrons of GaAsBi QDs decreases and the emission wavelength increases with the Bi contents and QD sizes. The emission wavelength can cover MWIR and LWIR ranges with proper Bi contents and QD sizes. The proposed structure provides a feasible way to fabricate MWIR and LWIR lasers.

提出了一种用于制造中波红外 (MWIR) 和长波红外 (LWIR) 激光器的 GaSb/GaAsBi II 型量子点结构。采用有限元方法研究了具有不同Bi含量和QD尺寸的所提出结构的序列分布和能带结构。发现应变分量ε _xx 随Bi 含量和高度而减小，随直径增大而增大，而分量ε _zz 反向变化。电荷载流子在 GaAsBi QD 中的电子和 GaSb 中的空穴之间重新结合。GaAsBi QDs的电子基态能量随着Bi含量和QD尺寸的增加而降低，发射波长增加。发射波长可以覆盖 MWIR 和 LWIR 范围，具有适当的 Bi 含量和 QD 尺寸。所提出的结构为制造 MWIR 和 LWIR 激光器提供了一种可行的方法。