Theoretical calculation of spatial variation of the transmission coefficient of closed carbon nanotubes

Xanthakis, JP; Kokkorakis, GC

dc.contributor.author	Xanthakis, JP	en
dc.contributor.author	Kokkorakis, GC	en
dc.date.accessioned	2014-03-01T02:43:00Z
dc.date.available	2014-03-01T02:43:00Z
dc.date.issued	2004	en
dc.identifier.issn	0142-2421	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/31176
dc.subject	Carbon nanotubes	en
dc.subject	Field emission	en
dc.subject	Local field	en
dc.subject	Transmission coefficient	en
dc.subject.classification	Chemistry, Physical	en
dc.subject.other	Carbon nanotubes	en
dc.subject.other	Computer simulation	en
dc.subject.other	Electron emission	en
dc.subject.other	Electron transitions	en
dc.subject.other	Electron transport properties	en
dc.subject.other	Fermi level	en
dc.subject.other	Field emission	en
dc.subject.other	Local field	en
dc.subject.other	Transmission coefficient	en
dc.subject.other	Surface reactions	en
dc.title	Theoretical calculation of spatial variation of the transmission coefficient of closed carbon nanotubes	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1002/sia.1730	en
heal.identifier.secondary	http://dx.doi.org/10.1002/sia.1730	en
heal.language	English	en
heal.publicationDate	2004	en
heal.abstract	We have calculated the spatial (angular) variation of the transmission coefficient of closed carbon nanotubes (CNT). For the evaluation of the local field outside the tip of the CNT we have used the method described in J. Appl. Phys. 2002; 91: 4580. In the present work we require the local field only inside the classically forbidden area, so we have managed to simplify our previous results and obtain an analytical form for the local potential. This potential was then inserted into the method of Das and Mahanty (Phys. Rev. B 1987; 36: 898) to obtain the transmission coefficient T(theta) at an angle theta to the axis of the tube. We have found a substantial angular variation of T(theta), the determining factor being the local field at the surface of the CNT and, to a lesser extent, the radius of the tube. Decreasing the local field increases the directionality of T(theta) but also decreases the current by several orders of magnitude so that a compromise between directionality and value of the current has to be sought. The directionality also increases with decreasing radius of the tube. The ratio of the height to the radius (h/R) of the CNTs per se plays a minor role, i.e. if one compares CNTs with different h/R but the same local field then minor changes are found. Copyright (C) 2004 John Wiley Sons, Ltd.	en
heal.publisher	JOHN WILEY & SONS LTD	en
heal.journalName	Surface and Interface Analysis	en
dc.identifier.doi	10.1002/sia.1730	en
dc.identifier.isi	ISI:000222377800007	en
dc.identifier.volume	36	en
dc.identifier.issue	5-6 SPEC. ISS.	en
dc.identifier.spage	391	en
dc.identifier.epage	394	en