tailieunhanh - Báo cáo hóa học: " Electrical Conductivity Studies on Individual Conjugated Polymer Nanowires: Two-Probe and Four-Probe Resu"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Electrical Conductivity Studies on Individual Conjugated Polymer Nanowires: Two-Probe and Four-Probe Resu | Nanoscale Res Lett 2010 5 237-242 DOI s11671-009-9471-y NANO EXPRESS Electrical Conductivity Studies on Individual Conjugated Polymer Nanowires Two-Probe and Four-Probe Results Yun Ze Long Jean Luc Duvail Meng Meng Li Changzhi Gu Zongwen Liu Simon P. Ringer Received 20 August 2009 Accepted 14 October 2009 Published online 13 November 2009 to the authors 2009 Abstract Two- and four-probe electrical measurements on individual conjugated polymer nanowires with different diameters ranging from 20 to 190 nm have been performed to study their conductivity and nanocontact resistance. The two-probe results reveal that all the measured polymer nanowires with different diameters are semiconducting. However the four-probe results show that the measured polymer nanowires with diameters of 190 95-100 35-40 and 20-25 nm are lying in the insulating critical metallic and insulting regimes of metal-insulator transition respectively. The 35-40 nm nanowire displays a metalinsulator transition at around 35 K. In addition it was found that the nanocontact resistance is in the magnitude of 104 X at room temperature which is comparable to the intrinsic resistance of the nanowires. These results demonstrate that four-probe electrical measurement is necessary to explore the intrinsic electronic transport properties of isolated nanowires especially in the case of metallic nanowires because the metallic nature of the measured Y. Z. Long H M. M. Li College of Physics Science Qingdao University 266071 Qingdao China e-mail J. L. Duvail Institut des Materiaux Jean Rouxel CNRS Universite de Nantes 44322 Nantes France C. Gu Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100190 Beijing China Z. Liu S. P. Ringer Australian Key Centre for Microscopy and Microanalysis The University of Sydney Sydney NSW 2006 Australia nanowires may be coved by the nanocontact resistance that cannot be excluded by a two-probe .