Surface acoustic wave mediated carrier injection into individual quantum post nano emitters
Surface acoustic wave mediated carrier injection into individual quantum post nano emitters
复制标题
表面声波介导的载流子注入单个量子后纳米发射器
作者：
Stefan Völk;F. Knall;F. J. Schülein;T. Truong;Hyochul Kim;P. Petroff;A. Wixforth;H. Krenner
由表面声波（SAW）引起的声电荷传输被用来解离光生激子。在宏观距离上，电子和空穴依次注入远程定位的、隔离的高质量量子发射器，即自组装的量子柱。与在量子柱位置处的直接光泵浦相比，该过程被发现非常高效，并且在高声功率下表现出更高的稳定性。这些特性分别归因于发生电荷传输的宽矩阵量子阱以及远程配置中可注入的大量载流子。当SAW的传播方向和量子柱的位置反转时，这种泵浦量子柱的发射主要由中性激子的复合主导并且是完全定向的。
Acousto-electric charge conveyance induced by a surface acoustic wave (SAW) is employed to dissociate photogenerated excitons. Over macroscopic distances, both electrons and holes are injected sequentially into a remotely positioned, isolated and high quality quantum emitter, a self-assembled quantum post. This process is found to be highly efficient and to exhibit improved stability at high acoustic powers when compared to direct optical pumping at the position of the quantum post. These characteristics are attributed to the wide matrix quantum well in which charge conveyance occurs and to the larger number of carriers available for injection in the remote configuration, respectively. The emission of such pumped quantum posts is dominated by recombination of neutral excitons and fully directional when the propagation direction of the SAW and the position of the quantum post are reversed.