標題: Persistent currents in toroidal carbon nanotubes
作者: Lin, MF
Chuu, DS
電子物理學系
Department of Electrophysics
公開日期: 15-三月-1998
摘要: The geometric structure of the toroidal carbon nanotubes (TCN's) determines the electronic structure and thus the characteristics of the persistent current. Such current is caused by the magnetic flux phi through TCN's. The semiconducting TCN's exhibit diamagnetism at small phi, which is in great contrast with paramagnetism of the metallic TCN's. The induced magnetic moment is proportional to the toroid radius, but independent of the toroid width. The magnetic response is weak, while it is much stronger than that of a mesoscopic semiconductor or metal ring. The persistent current is a linearly periodical function of phi, with a period phi(0)(hc/e). Such an oscillation is the manifestation of the Aharonov-Bohm (AB) effect. Temperature (T) does not destroy the periodical AB oscillation, although it would significantly reduce the persistent currents. The Zeeman splitting may lead to the destruction of the periodicity at very large phi. A larger TCN at lower T and phi is relatively suitable for verifying the AB effect.
URI: http://hdl.handle.net/11536/32726
ISSN: 0163-1829
期刊: PHYSICAL REVIEW B
Volume: 57
Issue: 11
起始頁: 6731
結束頁: 6737
顯示於類別:期刊論文