有机量子阱的光学性质

采用多源有机分子气相沉积系统(OMBD)制备了Alq₃，PBD/Alq₃，PBD/Alq₃/PBD单层、双层以及量子阱结构，利用电化学循环伏安法和吸收光谱、荧光光谱研究了量子阱的类型和样品的光致发光特性.电化学循环伏安法和吸收光谱的测量结果表明，PBD/Alq₃有机量子阱为Ⅰ型量子阱结构.荧光光谱的研究结果表明，单层Alq₃的光致发光峰不随Alq₃厚度变化而变化；但是双层PBD/Alq₃结构光致发光峰随Alq₃厚度的减小而发生蓝移；同样对于PBD/Alq₃/PBD量子阱结构光致发光峰随Alq₃厚度的减小而发生蓝移.对引起光谱蓝移的原因进行了讨论. 关键词： 有机量子阱 光谱蓝移

Optical property of organic quantum well structures

Single layer Alq₃, double layer PBD/Alq₃ and quantum well PBD/Alq₃/PBD structures have been grown by organic molecular beam deposition. Energy levels and optical property of these samples are determined by cyclic voltammetry, optical absorption and photoluminescence (PL). Cyclic voltammetry and optical absorption results indicate that PBD/Alq₃/PBD structures can be classified as type I quantum well. The PL experimental results indicate that PL peak, of single layer Alq₃ structures do not shift to higher energy with decreasing layer thickness. However, for double layer PBD/Alq₃ and quantum well PBD/Alq₃/PBD structures, PL peaks shift to higher energy with decreasing layer thickness. The reason for blue shift of PL in organic quantum well structures is discussed in light of the theoretical and experimental results published in the literature.