Nanoscale thermal analysis of InGaAs quantum well based semiconductor disk laser with different pump geometry

Abstract

Using the finite element method, thermal effects including the maximum temperature, the heat flux and the temperature gradient in the active region of semiconductor disk lasers with front and end pumped geometry are numerically analyzed at the first time. Nanoscale thermal conductivities of the multiple quantum wells and the distributed Bragg reflector are used to overcome the underestimate of the temperature rise which comes from the use of the weighted average of the bulk thermal conductivities in the previous works, and the calculated results are compared with the corresponding experiments. The maximum temperature of quantum wells in active region with end pump is always higher than that with front pump under same pump power. Because of its better mode matching, output powers of the end pumped laser are bigger than that of the front pumped laser when the pump power is relatively lower and the thermal rollover of laser has not happened. In comparison, the front pumped laser can tolerate much bigger pump power and produce much higher output power thanks to its better heat dissipation.