Maximum heat-sink temperature for CW operation of a double-heterostructure semiconductor injection laser

Assuming that the temperature dependence of the threshold current for pulsed operation is known, an analytical expression for the maximum heat-sink temperature, T_hm, for CW operation of the laser can be derived. The maximum heat-sink temperature is expressed in terms of the characteristic temperature T₀, the room-temperature threshold current for pulsed operation I₀ , the equivalent effective thermal resistance θ, and the equivalent effective series electrical resistance r of the device. It is shown that the values of T_hm can be enhanced by increasing the value of T₀ or by decreasing the values of I₀, θ, and r