%0 Journal Article
%T Difference in electric conduction of monocrystal and polycrystal graphite<br>单晶石墨、多晶石墨电导行为的差异
%A wang Zhi-Ming
%A Xu Qing-Yu
%A Zhang Shi-Yuan
%A Xing Ding-Yu
%A Du You-Wei
%A <br>王志明
%A 徐庆宇
%A 张世远
%A 邢定钰
%A 都有为
%J 物理学报
%D 2007
%I 
%X In this paper, we report the difference in electric conduction of monocrystal and polycrystal graphite. Under a magnetic field of 8.15T, the positive magnetoresistance ratio of monocrystal and polycrystal graphite samples are found to be 69400%, 170% respectively at 4.5K. The polycrystal graphite presents accordingly the insulator-like character in a wide interval of temperature under 0 and 8T applied magnetic field, but the magnetic-field-correlated semimetal-insulator-like Transition has been reported for the monocrystal graphite (highly oriented pyrolitic graphite, HOPG). On analysis, it is revealed that large difference in electric conduction originates predominantly from the Coulomb interaction in HOPG graphite layers in contrast with the crystal interface scattering in the polycrystal graphite.
%K semimetal graphite
%K semimetal-insulator-like transition<br>半金属石墨
%K 类半金属-绝缘体型转变
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=29DF2CB55EF687E7EFA80DFD4B978260&aid=6A5032AB10B21C0A&yid=A732AF04DDA03BB3&vid=014B591DF029732F&iid=B31275AF3241DB2D&sid=D39FFD36CB6E3A34&eid=F373DAB2584041B8&journal_id=1000-3290&journal_name=物理学报&referenced_num=0&reference_num=13