Optical Control of Internal Electric Fields in Band Gap-Graded InGaN Nanowires

详细信息    查看全文

• 作者：N. Erhard ; A. T. M. Golam Sarwar ; F. Yang ; D. W. McComb ; R. C. Myers ; A. W. Holleitner
• 刊名：Nano Letters
• 出版年：2015
• 出版时间：January 14, 2015
• 年：2015
• 卷：15
• 期：1
• 页码：332-338
• 全文大小：455K
• ISSN：1530-6992

文摘

InGaN nanowires are suitable building blocks for many future optoelectronic devices. We show that a linear grading of the indium content along the nanowire axis from GaN to InN introduces an internal electric field evoking a photocurrent. Consistent with quantitative band structure simulations we observe a sign change in the measured photocurrent as a function of photon flux. This negative differential photocurrent opens the path to a new type of nanowire-based photodetector. We demonstrate that the photocurrent response of the nanowires is as fast as 1.5 ps.