title: The fermi level dependent electronic properties of the smallest (2,2) carbon nanotube.
abstract: A metal-semiconductor transition in the smallest (2,2) single-wall carbon nanotube (SWNT) is predicted theoretically as a function of gate voltage. By hole-doping (or heavy electron-doping), the energy gap of a neutral (2,2) SWNT vanishes with structural change, and the (2,2) SWNT becomes metallic. The (2,2) tube assumes a doubly degenerate ground state around the charge neutral condition with an energy barrier, while this tube has only one nondegenerate metallic ground state over an energy window of -0.12 to +0.40 eV. Because of a high density of states at the Fermi energy for hole-doped (2,2) SWNTs, a possible superconducting transition is expected.
authors: Department of Physics, Tohoku University, Sendai 980-8578, Japan. lcyin@imr.ac.cn
authors: Li-Chang
authors: LC
authors: Yin
authors: Riichiro
authors: R
authors: Saito
authors: Mildred S
authors: MS
authors: Dresselhaus