Temperature and current dependences of the lasing spectrum's width of quantum dot lasers

Dependences of the lasing spectrum's width of lasers based on arrays of self-organized InAs/InGaAs quantum dots on the temperature and output power have been experimentally studied. A theoretical analysis and simulation of the experimental results have been performed and the possibility of an adequate analytical description of the power and temperature dependences of the lasing line width in terms of the model developed has been demonstrated. It is shown that the main cause of the broadening of the lasing spectrum at low temperatures is the gain saturation in quantum dots as a result of the increase in the average carrier's escape and capture times.