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arXiv · 0808.1914

Unusually strong space-charge-limited current in thin wires

A. Alec Talin·François Léonard·B. S. Swartzentruber·Xin Wang·Stephen D. Hersee
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Abstract

The current-voltage characteristics of thin wires are often observed to be nonlinear, and this behavior has been ascribed to Schottky barriers at the contacts. We present electronic transport measurements on GaN nanorods and demonstrate that the nonlinear behavior originates instead from space-charge-limited current. A theory of space-charge-limited current in thin wires corroborates the experiments, and shows that poor screening in high aspect ratio materials leads to a dramatic enhancement of space-charge limited current, resulting in new scaling in terms of the aspect ratio.

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A. Alec Talin, François Léonard, B. S. Swartzentruber, Xin Wang, Stephen D. Hersee. 2008-08-13. Unusually strong space-charge-limited current in thin wires. https://doi.org/10.1103/physrevlett.101.076802

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