【摘要】 给出基于GaN量子阱材料的远红外量子级联激光器,其优越性表现在AlGaN/GaN量子阱中,超快的纵向光学声子散射能够迅速的消除激光低能态的布居数,GaN的大纵向光学声子能量(~90 meV)能有效地减少高温下产生激光低能态的热布居.理论分析显示,用一个相对较低的阈值电流密度(832 A/cm2)就能在室温下产生50/cm的阈值光学增益.还发现这种结构的特征温度T0高于136 K.更多还原

【Abstract】 It was proposed that the idea of developing far infrared quantum cascade lasers(QCLs) with GaN-based quantum well(QW) structures has significant advantage over the currently demonstrated far infrared lasers based on GaAs-based material system.While the ultrafast longitudinal optical(LO) phonon scattering in AlGaN/GaN QWs can be used for the rapid depopulation of the lower laser state,the large LO-phonon energy(～90 meV) can effectively reduce the thermal population of the lasing states at higher temperatures.The analysis of one particular structure has shown that a relatively low threshold current density of 832 A/cm~2 can provide a threshold optical gain of 50/cm at room temperature.It has been also found that the characteristic temperature T-0 in this structure is as high as 136 K.更多还原