Theoretical study on photoelectric emission of AlxGa1-xAs nanowire array photocathode with variable Al component under external electric field

• Published in: Chemical physics letters Vol. 804; p. 139903
• Main Authors: Sun, Yan, Liu, Lei, Cheng, Hongchang, Lv, Zhisheng, Zhangyang, Xingyue, Guo, Xin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2022
• Subjects: AlxGa1-xAs; External electric field; Nanowire array; Photocathode; External electric field; AlxGa1-xAs; Nanowire array; Photocathode
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2022.139903

[Display omitted] •The variable Al component AlxGa1-xAs nanowire model is established and the quantum efficiency of nanowire is calculated.•Al component in the second sublayer of AlxGa1-xAs nanowire can greatly affect the quantum efficiency of the array.•Small external electric field can improve the quantum efficiency. The internal electric field formed by the AlxGa1-xAs structure with variable Al component can promote the carrier migration to the top surface of the nanowire to improve the photoelectric emission of the nanowire array. Similarly, under the action of the external electric field, the carrier inside the nanowire drift towards the top surface and change the trajectories of electrons between the nanowires. In this paper, the variable Al component AlxGa1-xAs nanowire model was established by using COMSOL Multipysics software, and the quantum efficiency of the nanowire was calculated based on the two-dimensional continuity equation with Matlab. The results show that the Al component in the second sublayer of AlxGa1-xAs nanowire can greatly affect the quantum efficiency of the array. Small external electric field can improve the quantum efficiency, while large external electric field and inclined light irradiation can reduce the quantum efficiency.