Two-Step Photocarrier Generation in InAs/GaAs Quantum Dot Superlattice Intermediate Band Solar Cell

被引：0

作者：

Kada, Tomoyuki ^{[1
]}

Tanibuchi, Taizo ^{[1
]}

Asahi, Shigeo ^{[1
]}

Kaizu, Toshiyuki ^{[1
]}

Harada, Yukihiro ^{[1
]}

Kita, Takashi ^{[1
]}

Tamaki, Ryo ^{[2
]}

Okada, Yoshitaka ^{[2
]}

Miyano, Kenjiro ^{[2
]}

机构：

[1] Kobe Univ, Dept Elect & Elect Engn, Grad Sch Engn, Nada Ku, 1-1 Rokkodai, Kobe, Hyogo 6578501, Japan

[2] Univ Tokyo, Res Ctr Adv Sci & Technol, Meguro Ku, Tokyo 1538904, Japan

来源：

2015 IEEE 42ND PHOTOVOLTAIC SPECIALIST CONFERENCE (PVSC) | 2015年

关键词：

photoluminescence; photovoltaic cells; quantum dots; superlattices;

D O I：

暂无

中图分类号：

TE [石油、天然气工业]; TK [能源与动力工程];

学科分类号：

0807 ; 0820 ;

摘要：

We studied the two-step photon absorption (TSPA) process in InAs/GaAs quantum-dot superlattice (QDSL) solar cells. The photoluminescence (PL) and its excitation spectrum (PLE) showed the contribution of the higher excited states (ESs) forming the miniband of the QDSLs above the in homogeneously distributed ground states (GSs). TSPA of subbandgap photons efficiently occurs when electrons are pumped from the valence band (VB) to the higher ESs. When the higher ESs were resonantly excited, the superlinear excitation power dependence of the PL intensity appeared. Moreover, time-resolved PL showed that the electron lifetime is extended. These results demonstrate that the excited electron and hole separately relax into QDSLs, and thereby, enhancing the second sub-bandgap absorption.

引用

页数：4

共 10 条

[1] Apparent stretched-exponential luminescence decay in crystalline solids [J].