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J. Phys. Soc. Jpn. 74 (2005) pp. 515-518  |Next Article|  |Table of Contents|
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Nonlinear Charging and Transport Times in Doped Nanotubes Junctions

Keivan Esfarjani, Amir A. Farajian1, Yoshiyuki Kawazoe1 and Siu Tat Chui2

Department of Physics, Sharif University of Technology, Tehran 11365-9161, Iran
1IMR, Tohoku University, Sendai 980-8577
2BRI, University of Delaware, Newark, DE 19716, U.S.A.

(Received September 1, 2004)

The nonlinear capacitance in doped nanotube junctions is calculated self consistently. A negative differential capacitance is observed when the applied bias becomes larger than the pseudogap of the metallic armchair nanotube. For this device, one can deduce a relaxation time of approximately 0.1 fs. Because of its negative differential resistance (NDR), a switching time of less than a femtosecond, i.e., at least three orders smaller than present-day switching times, can also be estimated. This effect is important in designing ultrafast nano-electronic components. ©2005 The Physical Society of Japan

KEYWORDS: nanotube, junction, transport, device, response time
URL: http://jpsj.ipap.jp/link?JPSJ/74/515/
DOI: 10.1143/JPSJ.74.515


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