Mid-infrared photoluminescence revealing internal quantum efficiency enhancement of type-I and type-II InAs core/shell nanowires

Authors：Chen, Xiren^*; Alradhi, H.; Jin, Zh. M.; Zhu, Liangqing; Sanchez, A. M.; Ma, Shufang; Zhuang, Qiandong^*; Shao, Jun^*

Source：Optics Letters, 2022, 47(19): 5208-5211.

DOI：10.1364/OL.473154

• EMISSION

Internal quantum efficiency (IQE) is an important figure of merit for photoelectric applications. While the InAs core/shell (c/s) nanowire (NW) is a promising solution for efficient quantum emission, the relationship between the IQE and shell coating remains unclear. This Letter reports mid -infrared PL measurements on InAs/InGaAs, InAs/AlSb, and InAs/GaSb c/s NWs, together with bare InAs NWs as a ref-erence. Analyses show that the IQE is depressed by a shell coating at 9 K but gets improved by up to approximately 50% for the InGaAs shell coating at 40 -140 K and up to approx-imately 20% beyond 110 K for the AlSb shell. The effect is ascribed not only to the crystal quality but more importantly to the radial band alignment. The result indicates the high -temperature IQE improvement of the type-I and type-II c/s NWs and the appropriateness of the mid-infrared PL analy-ses for narrow-gap NW evaluation.

• Institution
  中国科学院; 陕西科技大学