Negative characteristic temperature of GaN-based blue laser diode investigated by numerical simulation

摘要

GaN-based blue laser diodes (LDs) may exhibit anomalous temperature characteristics such as a very high or negative characteristic temperature (T_o). In this work, the temperature characteristics of blue LDs having InGaN double quantum-well (QW) active region are investigated using numerical simulation. It is found that the T_o is greatly influenced by the n-type doped barrier between the QWs and a negative T_o can be observed for the LD structure with a heavily doped barrier. The negative T_o of InGaN blue LDs is mainly attributed to the decrease of the Auger recombination rate at the p-side QW with increasing temperature as a result of the thermally enhanced hole transport from the p-side to the n-side QW.