The Design Of Driving Circuit And Analyze Of Circuit Model For Quantum Cascade Laser

Quantum cascade laser (QCL) is a new type of quantum-well lasers. It has the advantage of the lasing wavelength adjusted very wide range. QCL offers an ideal source for mid and far-infrared laser emission. There was very different from ordinary semiconductor laser in light-emitting mechanism. An equivalent circuit model was derived on the base Of rate equation of QCL. 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.The stability of the laser injection current and the operating temperature has a direct, significant impact on the output of QCL, so it is of great importance to develop a high stability laser driving source. This thesis analyzes the main factor that affected the stable output of QCL and the required technical qualifications for the system have been determined and consequently, the driver system for QCL is designed based on the study of the principle and the characteristics of QCL. This driver system includes a current driver control section and a temperature control section.Finally, the performance tests of this drive power system for QCL are done. The experimental results showed that the technical qualifications have met the design requirements expected.