Theoretical Study of the Operation and Performance of a Terahertz Quantum Cascade Laser Using Density Matrix Method

Publication Issue: 
Volume 37, Issue 1, 2016
Page No: 
Date Received: 
Tuesday, May 3, 2016
Authors' Name: 
Mohd Asmu'i Mohd Akil
Amiruddin Shaari
Khalid Akabli
Mohd Khalid Kasmin
Zulkafli Othaman
Authors' Affiliation and Address: 
Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia
Docteur En Physique Theorique Et Modelisation, France
Terahertz (THz) quantum cascade lasers (QCL) are currently increasing its popularity in optoelectronic applications. It is expected to become the main source of emerging terahertz radiation technology and applications. However to produce the device within the application specification is costly and time consuming. Thus a prediction tool is needed to overcome the problems faced in designing and producing THz QCL within the required optical emission. The density matrix method is used to calculate the electronic and optical properties such as population density, current-voltage (I-V) and gain curves of this device. The results from this study were compared to the experimental ones conducted by previous researchers. From the calculation, the value of the gain is 20 cm-1 when the population inversion occurs starting from 400 A cm-2. Meanwhile the loss occurs below 320 A cm-2. As a conclusion, it is demonstrated that this method has the capability to explain the operation as well as to predict the performance of the THz QCL device.