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arXiv · 1108.1723

Electric Current Focusing Efficiency in Graphene Electric Lens

Weihua Mu·Gang Zhang·Yunqing Tang·Zhongcan Ou-Yang
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Abstract

In present work, we theoretically study the electron wave's focusing phenomenon in a single layered graphene pn junction(PNJ) and obtain the electric current density distribution of graphene PNJ, which is in good agreement with the qualitative result in previous numerical calculations [Science, 315, 1252 (2007)]. In addition, we find that for symmetric PNJ, 1/4 of total electric current radiated from source electrode can be collected by drain electrode. Furthermore, this ratio reduces to 3/16 in a symmetric graphene npn junction. Our results obtained by present analytical method provide a general design rule for electric lens based on negative refractory index systems.

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Weihua Mu, Gang Zhang, Yunqing Tang, Zhongcan Ou-Yang. 2011-08-08. Electric Current Focusing Efficiency in Graphene Electric Lens. https://doi.org/10.1088/0953-8984%2F23%2F49%2F495302

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