Model And PSpice Simulation Of Quantum Well Laser Device

The quantum well structure is the core part of the optoelectronic semi-conductor device. It is the important foundation of the optoelectronic integrated circuit. At present, in the area of optoelectronic, people in the world are concentrating on the development of quantum well optoelectronic device. The quantum well laser device (QW—LD) is the entering edge of semiconductor laser. On this account, studying the characteristic of the QW—LD has a great significance.Firstly, this text introduced the foundation knowledge of the QW—LD, then studied the two typical model (the D.S.Gao model and the G.Rossi model )of QW— LD. On the base of that ,we use the PSpice simulation software to imitate the various characteristic of the QW—LD . But during the imitating, we found that they both had their shortages. For example, the D.S.Gao model can not distinguish the distinctions of each well, but the G.Rossi model can do that, but it can not be used when there are too many wells.Secondly, the D.S.Gao model is under the premise that the reflectivity values of the laser's two ends are the same. But actually, the two reflectivity values are usually different, particularly for the laser device in the OEIC (Opto-electronic Integrated Circuit).Usually one end is the cleavage surface, but the other is the etched surface. As the result, the two reflectivity values are different. In order to accord with the fact, D.S.Gao model suggest to add an adjustment parameter to remedy the shortage. But the parameter is very difficult to choose exactly. But this text considered it when gave the relation between the output power and density of photoelectron, aslo find out the relevant equations.Thirdly, this text also gave a temperature parameter to remedy the G.Rossi model. Though the G.Rossi model contains the temperature parameter, when the writer used it to test the QW—LD's direct current characters, the outputs are exactly coincident. And we know that when the temperature increased, the valve value current of the QW—LD went to enlarge, the outside quantum efficiency went to decrease. In order to remedy this error, this text gave a temperature revisingparameter.Lastly, the text deduced the formula to count the best well number of the QW— LD, also it imitated the relations between the valve value current and cavity length, having found out that when the cavity diminished greatly, the valve value current also diminished greatly, but existed thus a time, a certain time that the cavity length continue to diminish, but the valve value current turn to aggrandize quickly .And at that time, the power character of the quantum cavity expressed an obvious damping, which was tally with the actual circumstance.