量子级联激光器调制特性的电路模拟

量子级联激光器(QCL)是波长范围在中远红外的一类新型激光器，到目前为此，对于它的脉冲响应及调制响应等动态特性了解并不是很深入，为此以贝尔实验室在1994年发明的量子级联激光器器件模型为基础，通过分析量子级联激光器中的电子在多量子阱间输运及跃迁的单极行为，得到它的速率方程。以此为基础，通过用电路元素对方程进行改造，建立起其相应的等效电路模型，利用PSPICE电路模拟软件进行模拟仿真，得到了它的调制响应特性，对可能影响其调制特性的一些因素如各阱之间的弛豫时间进行了讨论，并与其它类型激光器作了比较，发现量子级联激光器的动态性能并不优良，而这一点应缘于其独特的激射能级结构。

Circuit Simulation for Modulation Characteristics of Quantum Cascade Semiconductor Laser

Quantum cascade laser (QCL) is a new-style laser whose wavelength remains in middle and far infrared. Hitherto its dynamic characters like pulse and modulation responses haven't been well acquainted. To ascertain this, an equivalent circuit model was derived on the base of rate equation of QCL that is invented by Bell Lab in 1994 by analyzing the unipolar transportation and transition behaviour of electrons in multiply quantum well, and the modulation response of QCL is gotten in the circuit simulation program PSPICE. Consequently some factors such as transition time between wells have been analyzed which could affect the modulation character of QCL.At last its dynamic character is found to be unexcellent compared with other lasers because of its peculiar energy band structure.