Eigenstates and transmission coefficients of finite-sized carbon nanotubes

Compernolle, Steven; Chibotaru, Liviu F.; Ceulemans, Arnout

doi:10.1063/1.1587691

Cited by 36 publications

(21 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…By cutting a very long CN into a shorter one, a quasi-zero-dimensional finite CN is obtained. A scanning tunneling microscope has been utilized to produce finite CNs with length w $ 100 # A.2) The quantum-size effects cause finite CNs to exhibit special physical properties, e.g., geometric structures, 3) electronic structures, 4-7) optical properties, 8,9) magnetic 10-12) and quantum transport properties. 13) Many theoretical and experimental studies had been carried out on magnetoelectronic properties of infinite CNs.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Magnetization of Finite Carbon Nanotubes

Chen

Chang²,

Hwang

et al. 2005

J. Phys. Soc. Jpn.

View full text Add to dashboard Cite

Magnetoelectronic properties of finite carbon nanotubes (CNs) are studied for an arbitrary field direction. They are strongly affected by the nanotube geometry (length, radius; boundary structure), the magnitude and direction of the magnetic field, the Zeeman effect, and the temperature. Geometric structures determine electronic structures and magnetic properties, which thus leads to three types of energy gaps and induced magnetic fields. The critical angle, which corresponds to the change of magnetism, exists in armchair CNs, but not in zigzag CNs. It also depends on the length and the radius of CNs. Finite CNs are very different from infinite CNs. Zeeman splitting could induce complete energygap modulation, a drastic change in magnetization, and a gigantic paramagnetic response for all zigzag CNs. The predicted results are observable even at room temperature.Quasi-one-dimensional carbon nanotubes (CNs) 1) have attracted much attention due to their very interesting properties and high potential for practical applications. A single-walled CN is a rolled-up 2D graphite sheet in the cylindrical form. By cutting a very long CN into a shorter one, a quasi-zero-dimensional finite CN is obtained. A scanning tunneling microscope has been utilized to produce finite CNs with length w $ 100 # A.2) The quantum-size effects cause finite CNs to exhibit special physical properties, e.g., geometric structures, 3) electronic structures, 4-7) optical properties, 8,9) magnetic 10-12) and quantum transport properties. 13) Many theoretical and experimental studies had been carried out on magnetoelectronic properties of infinite CNs. 14-21) Without a magnetic field B, whether CNs are metallic or semiconducting depends on their radius, chirality, and curvature effects. For example, (m, m) armchair CNs, 20) (m ¼ 3I, 0) zigzag CNs, and (m 6 ¼ 3I, 0) zigzag CNs are, respectively, gapless metals, narrow-gap semiconductors, and moderate-gap semiconductors (I is an integer). Infinite CNs drastically change from metals to semiconductors or vice versa, when they exist in a uniform magnetic field. 16) From the theoretical predictions, 17,18) the metallic and narrow-gap (moderate-gap) systems are paramagnetic (diamagnetic) with magnetic field parallel to the nanotube axis (B k kẑ z). All infinite CNs are diamagnetic in the presence of the perpendicular magnetic field (B ? ). Moreover, the dependence of the magnetic response on the radius is very weak.In this work, the tight-binding model with the curvature effects is used to study magnetoelectronic properties of finite CNs with any field direction. The dependence of magnetoelectronic properties on the magnitude (B) and direction () of the magnetic field, the geometric structures (length, radius r; boundary structures), Zeeman splitting, and the temperature (T) are investigated. Comparison with results for infinite CNs are also performed.Finite armchair and zigzag CNs are chosen for a model study. An armchair and a zigzag CN, as shown in Figs. 1(a) and 1(b), respectively, is obtained by rolling ...

show abstract

mentioning

confidence: 99%

“…2) The quantum-size effects cause finite CNs to exhibit special physical properties, e.g., geometric structures, 3) electronic structures, [4][5][6][7] optical properties, 8,9) magnetic [10][11][12] and quantum transport properties. 13) Many theoretical and experimental studies had been carried out on magnetoelectronic properties of infinite CNs.…”

mentioning

confidence: 99%

Magnetization of Finite Carbon Nanotubes

Chen

Chang²,

Hwang

et al. 2005

J. Phys. Soc. Jpn.

View full text Add to dashboard Cite

show abstract

“…We can therefore write a compact expression for the energy of all MOs with a nonzero value of x: (13) or, substituting the explicit expression for γ,…”

Section: T T …mentioning

confidence: 99%

“…He also noted the Tamm nature of these states in analogy with the surface states that arise in the problem of a semi infinite crystal [12]. The most systematically analytic estimates for the molecular orbitals of edge NT frag ments (including localized states) were considered in works of Compernolle [13], who used the transfer matrix technique to find them.…”

Section: Introductionmentioning

confidence: 99%

Potential magnetic properties of nanotubes (n, 0) with Klein and Fujita edges

Luhavaya

Павлов

Ermilov

et al. 2012

Russ. J. Phys. Chem.

View full text Add to dashboard Cite

Analytical solutions for localized states of zigzag type nanotube (NT) fragments with various combinations of Klein and Fujita borders are considered using the Hückel approach. It is shown that the equations for determining molecular orbitals (MOs) in systems with two Klein edges are similar to equations for systems with two Fujita edges. An analytical formula for the energies of all π MOs is obtained for systems that have a Klein edge on one side and a Fujita edge on the other. It is established that these systems have n orbitals with energy α that are localized on the Fujita and Klein edges in dependence on the MO symmetry. The degeneracy of edge orbitals indicates that there is a tendency toward single occupancy of them and to the appearance of spin (magnetic) properties. In addition, the energies of the states of different multiplicity for NT fragments (8, 0) are calculated using the CASSCF approach. It is shown that the ground state has a mul tiplicity of 9, as was also indicated by estimates obtained using the density functional method (B3LYP). It is concluded that zigzag type NTs with asymmetric edges have a tendency to exhibit spin properties. It is noted that the construction of nanoscale magnetic materials based on them is very promising.

show abstract

“…The chemical and physical properties of SWCNT and related materials have been investigated experimentally and theoretically. [2][3][4][5][6] SWCNT has exclusive mechanical and electronic properties, with rigid skeletons sandwiched between overlapping unsaturated molecular orbitals (MOs) 6 essentially formed by the p atomic orbitals of carbon. Particularly it is one of the most promising candidates for construction of nanoscale electronic devices owing to their special properties and intriguing applications in many fields.…”

Section: Introductionmentioning

confidence: 99%

Structure and Properties of Dual-Ti-Doped Single-Walled Carbon Nanotubes Within Density Functional Theory

Yu¹,

Zhang²,

Dong³

et al. 2011

Jnl of Comp & Theo Nano

View full text Add to dashboard Cite

Different types of substitution of one or two carbon atoms in (7, 7) single-walled carbon nanotube (SWCNT) by two Titanium atoms have been systemically studied within density functional theory based method. Fourteen different dual-Ti-doped SWCNT fragments were investigated and conformation IX doped with a Ti dimer is the most stable conformation. According to natural population and frontier molecular orbital analyses, the relative substitution positions of those two Ti atoms have significant impact on the local structure of doping site. Spin polarization occurs at the Ti atoms and such phenomenon helps to build new magnetic materials based on Ti-doped SWCNT. The special structure of the Ti-doped SWCNT with a C atom replaced by a Ti dimer in an insertion fashion brings about new properties to Ti-doped SWCNTs.

show abstract

Eigenstates and transmission coefficients of finite-sized carbon nanotubes

Cited by 36 publications

References 26 publications

Magnetization of Finite Carbon Nanotubes

Magnetization of Finite Carbon Nanotubes

Potential magnetic properties of nanotubes (n, 0) with Klein and Fujita edges

Structure and Properties of Dual-Ti-Doped Single-Walled Carbon Nanotubes Within Density Functional Theory

Contact Info

Product

Resources

About