High-conducting magnetic nanowires obtained from uniform titanium-covered carbon nanotubes

We have shown that a semiconducting single-wall carbon nanotube (SWNT) can be covered uniformly by titanium atoms and form a complex but regular atomic structure. The circular cross section changes to a squarelike form, and the system becomes metallic with high state density at the Fermi level and with high quantum ballistic conductance. Metallicity is induced not only by the metal-metal coupling, but also by the band-gap closing of SWNT's at the corners of the square. Even more interesting is that uniform titanium-covered tubes have magnetic ground state with significant net magnetic moment. Our results have been obtained by the first-principles pseudopotential plane-wave calculations within the density-functional theory.

[1]  Charles M. Lieber,et al.  Synthesis and characterization of carbide nanorods , 1995, Nature.

[2]  D. Leitner,et al.  Thermal conduction through a molecule , 1999 .

[3]  Kong,et al.  Intrinsic electrical properties of individual single-walled carbon nanotubes with small band gaps , 2000, Physical review letters.

[4]  A. Ozpineci,et al.  Quantum effects of thermal conductance through atomic chains , 2001 .

[5]  S. Ciraci,et al.  Energetics and Electronic Structures of Individual Atoms Adsorbed on Carbon Nanotubes , 2004 .

[6]  Jijun Zhao,et al.  Magnetism of transition-metal/carbon-nanotube hybrid structures. , 2003, Physical review letters.

[7]  J. M. van Ruitenbeek,et al.  Formation and manipulation of a metallic wire of single gold atoms , 1998, Nature.

[8]  T Yildirim,et al.  Tunable adsorption on carbon nanotubes. , 2001, Physical review letters.

[9]  Vieira,et al.  Plastic Deformation of Nanometer-Scale Gold Connective Necks. , 1995, Physical review letters.

[10]  Yukihito Kondo,et al.  Quantized conductance through individual rows of suspended gold atoms , 1998, Nature.

[11]  S. Ciraci,et al.  Variable and reversible quantum structures on a single carbon nanotube , 2000, cond-mat/0011309.

[12]  Quantum heat transfer through an atomic wire , 1999, cond-mat/9908204.

[13]  Hongjie Dai,et al.  Metal coating on suspended carbon nanotubes and its implication to metal–tube interaction , 2000 .

[14]  S. Ciraci,et al.  Formation of quantum structures on a single nanotube by modulating hydrogen adsorption , 2003 .

[15]  Tekman,et al.  Theory of transition from the tunneling regime to point contact in scanning tunneling microscopy. , 1989, Physical review. B, Condensed matter.

[16]  S. Fan,et al.  Synthesis of Gallium Nitride Nanorods Through a Carbon Nanotube-Confined Reaction , 1997 .

[17]  Benedict,et al.  Hybridization effects and metallicity in small radius carbon nanotubes. , 1994, Physical review letters.

[18]  Hongjie Dai,et al.  Formation of metal nanowires on suspended single-walled carbon nanotubes , 2000 .

[19]  Zhong Lin Wang,et al.  Magnetic properties of Fe nanoparticles trapped at the tips of the aligned carbon nanotubes , 2001 .

[20]  S. Ciraci,et al.  Conductance through a single atom , 1997 .

[21]  Tekman,et al.  Theoretical study of transport through a quantum point contact. , 1991, Physical review. B, Condensed matter.

[22]  Oguz Gulseren,et al.  Systematic study of adsorption of single atoms on a carbon nanotube , 2003 .

[23]  A. Govindaraj,et al.  Barkhausen jumps and related magnetic properties of iron nanowires encapsulated in aligned carbon nanotube bundles , 2002 .

[24]  Hong Guo,et al.  Current-voltage characteristics of carbon nanotubes with substitutional nitrogen , 2002 .

[25]  Jackson,et al.  Atoms, molecules, solids, and surfaces: Applications of the generalized gradient approximation for exchange and correlation. , 1992, Physical review. B, Condensed matter.