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arXiv · 1502.03773

Optical control of internal electric fields in band-gap graded InGaN nanowires

N. Erhard·A. T. M. Golam Sarwar·F. Yang·D. W. McComb·R. C. Myers·A. W. Holleitner
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Abstract

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.

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N. Erhard, A. T. M. Golam Sarwar, F. Yang, D. W. McComb, R. C. Myers, A. W. Holleitner. 2015-02-12. Optical control of internal electric fields in band-gap graded InGaN nanowires. https://doi.org/10.1021/nl503616w

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