Methods for determination of thermal characteristics of semiconductor injection lasers

Methods are proposed for determining the thermal characteristics of injection lasers from the threshold currents under various operating conditions. A feature of these methods is the easy determination of the initial data required to calculate the thermal characteristics. It is found that some of the Joule heat released due to the resistance of a laser diode is efficiently removed by a heat sink and does not heat the active region. A method of determining the thermal power which results in heating of the active region is proposed. It is shown that neglect of this mechanism for removal of some of the heat can give rise to significant errors in the determination of the thermal characteristics.