Electrical Transport in Rings of Single-Wall Nanotubes: One-Dimensional Localization

2000 ◽  
Vol 84 (19) ◽  
pp. 4441-4444 ◽  
Author(s):  
H. R. Shea ◽  
R. Martel ◽  
Ph. Avouris
Keyword(s):  
Electrical Transport ◽  
One Dimensional ◽  
Single Wall Nanotubes

scholarly journals The potentials and challenges of electron microscopy in the study of atomic chains

2017 ◽  
Vol 78 (2) ◽  
pp. 20701
Author(s):  
Florian Banhart ◽  
Alessandro La Torre ◽  
Ferdaous Ben Romdhane ◽  
Ovidiu Cretu
Keyword(s):  
Electron Microscopy ◽  
Electrical Transport ◽  
In Situ Tem ◽  
Free Standing ◽  
One Dimensional ◽  
Resonant States ◽  
In Situ Experiments ◽  
Atomic Chains ◽  
Substantial Progress

The article is a brief review on the potential of transmission electron microscopy (TEM) in the investigation of atom chains which are the paradigm of a strictly one-dimensional material. After the progress of TEM in the study of new two-dimensional materials, microscopy of free-standing one-dimensional structures is a new challenge with its inherent potentials and difficulties. In-situ experiments in the TEM allowed, for the first time, to generate isolated atomic chains consisting of metals, carbon or boron nitride. Besides having delivered a solid proof for the existence of atomic chains, in-situ TEM studies also enabled us to measure the electrical properties of these fundamental linear structures. While ballistic quantum conductivity is observed in chains of metal atoms, electrical transport in chains of sp1-hybridized carbon is limited by resonant states and reflections at the contacts. Although substantial progress has been made in recent TEM studies of atom chains, fundamental questions have to be answered, concerning the structural stability of the chains, bonding states at the contacts, and the suitability for applications in nanotechnology.

INTERACTIONS OF THz VIBRATIONAL MODES WITH CHARGE CARRIERS IN DNA: POLARON-PHONON INTERACTIONS

2007 ◽  
Vol 17 (02) ◽  
pp. 293-309 ◽  
Author(s):  
DINAKAR RAMADURAI ◽  
TAKAYUKI YAMANAKA ◽  
YANG LI ◽  
MILANA VASUDEV ◽  
VISWANATH SANKAR ◽  
...  
Keyword(s):  
Charge Transport ◽  
Electrical Transport ◽  
Theoretical Calculations ◽  
Charge Trapping ◽  
Directed Assembly ◽  
Charge Carriers ◽  
Vibrational Modes ◽  
Electrical Transport Properties ◽  
One Dimensional ◽  
Phonon Absorption

This paper presents models and experimental measurements that shed light on THz-phonon mediated transport of polarons in biomolecules. Polaron transport in DNA has been considered recently in view of the expected derealization of charge carriers on a one-dimensional wire as well as the highly charged nature of DNA.1,2 An understanding of the electrical transport properties and THz-phonon interactions of biomolecules is important in view of DNA's potential applications both as electrically conductive wires and as structures that facilitate the chemically-directed assembly of massively integrated ensembles of nanoscale semiconducting elements into terascale integrated networks. Moreover, understanding these interactions provides information of the THz spectrum of vibrational modes in DNA. A primary focus of this paper is on charge transport in biomolecules using indirect-bandgap colloidal nanocrystals linked with biomolecules.3 Through a combination of theoretical and experimental approaches,4-7 this paper focuses on understanding the electrical properties and THz-frequency interactions of DNA. Moreover, this paper presents observed charge transport phenomena in DNA and discusses how these measurements are related to carrier scattering from the THz vibrational modes in DNA. Indeed, carrier transport in DNA is analyzed in light of theoretical calculations of the effects of THz-frequency phonon emission by propagating carriers, THz-frequency phonon absorption by propagating and trapped carriers, and effective mass calculations for specific sequences of the DNA bases.1-7 These studies focus on THz-phonon-mediated processes since an extra carrier on a one-dimensional chain minimizes its energy by forming an extended polaron, and since many biomolecules, including DNA, exhibit THz vibrational spectra.8 Accordingly, these calculations focus on THz-phonon-mediated processes. These results are discussed in terms of the role of THz-phonon-mediated charge trapping and detrapping effects near guanine-rich regions of the DNA as well as on the understanding and identification of DNA with specific base sequences that promote charge transport. As in previous studies, optical excitation is used to inject carriers into DNA wires. Moreover, this paper reports on the use of gel electrophoresis to study charge-induced cleavage of DNA and the related transport of charge in DNA. Phonon absorption and emission from polarons in DNA,9 is analyzed using parameters from the well-known Su-Schrieffer-Heeger Hamiltonian.

Effect of Morphology on the Electrical Transport Properties of Polyaniline Films for Electronic Applications

1997 ◽  
Vol 488 ◽  
Author(s):  
S. S. Hardaker ◽  
K. Eaiprasertsak ◽  
J. Yon ◽  
R. V. Gregory ◽  
G. X. Tessema
Keyword(s):  
Temperature Dependence ◽  
Electrical Transport ◽  
Chemical Reduction ◽  
Variable Range Hopping ◽  
Structure And Properties ◽  
Electrical Transport Properties ◽  
One Dimensional ◽  
Temperature Dependence Of Conductivity ◽  
Polyaniline Films ◽  
Dimensional Variable

AbstractAlthough it is well known that the oxidation state of polyaniline is an important characteristic, there are few reports of its influence on the development of morphology and electrical properties in fibers and films. In this work, differential scanning calorimentry is used in conjunction with measurements of temperature dependence of conductivity and thermoelectric power to elucidate the intimate relationship between structure and properties. By increasing the amount of chemical reduction of polyaniline solutions, films are prepared which exhibit a thermal transition between 300 and 385 °C, indicative of melting. Increasing the chemical reduction also increases the conductivity of iodine doped films. The most reduced film exhibited a semiconductor transport mechanism, while the other films could be modeled with a quasi-one dimensional variable range hopping mechanism. The temperature dependence of conductivity also showed increasing order for increasing reduction, consistent with the DSC results.

Size dependence in one-dimensional nano-materials and one-dimensional heterojunctions

2006 ◽  
Vol 931 ◽  
Author(s):  
Jing Zhu ◽  
Jun Luo ◽  
Changqiang Chen ◽  
Yu Shi ◽  
Xiaohua Liu ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Electrical Transport ◽  
Large Scale ◽  
Zno Nanowires ◽  
Nanowire Arrays ◽  
Surface Relaxation ◽  
Nano Materials ◽  
One Dimensional ◽  
Si Nanowire ◽  
Ag Nanowires

ABSTRACTOne-dimensional (1D) nano-materials have attracted a plenty of attention due to their novel structures and properties. Our group has carried out researches on synthesis, structure and property of 1D nano-materials, which are introduced in this paper. First, size effects on the crystal structure of Ag nanowires and on Young's modulus in [0001] oriented ZnO nanowires, respectively, have been revealed and modeled. The former is concerning the systemic energy of an individual Ag nanowire. The latter is caused by the surface stiffening effect arising from surface relaxation induced bond length contractions in the ZnO nanowires. Second, structures of 1D helical nano-materials including SWCNT (single-walled carbon nanotube), B-DNA and MWCNT (mutli-walled carbon nanotube) have been studied. It is shown that there is strong orientation dependence of diffraction intensities from SWCNT and B-DNA, which can even result in certain layer lines missing in their diffraction patterns. Also, it is demonstrated that high-resolution transmission electron microscope (TEM) images of sidewall regions of MWCNTs are not structural ones and from the interference of the {0002} and the {1011} diffraction waves. Third, arrays of four types of 1D heterojunctions have been synthesized. Among these 1D heterojunctions, the interfacial structures of the Ni/MWCNT/a-CNT(amorphous carbon nanotube) heterojunctions show that multiple outer walls in the MWCNTs can simultaneously participate in electrical transport. The electrical properties of the Ni/MWCNT/a-CNT and the Ag/a-CNT heterojunctions have been measured. As a result, it is found that the contacts between the Ag nanowires and the a-CNTs are ohmic ones with universal significance, and that each Ni/MWCNT/ a-CNT contains two diodes connected in series face-to-face. Moreover, most of the diodes have the most nearly ideal characteristics of Schottky contacts, indicated by quantitative analysis with the thermionic emission theory. Last, our group has developed a novel technique for rapidly producing large-area highly-oriented Si nanowire arrays on Si wafers by scratching the Si surface with metal nanoparticles near room temperature in HF solution. By this method, Si nanowires with desirable axial crystallographic directions, desirable doping characteristics and remarkable antireflection property can be readily obtained. The Si nanowire arrays have the potential applicability as an antireflective layer for photovoltaic devices and optical detectors. Furthermore, a combination of this method and the nanosphere lithography has been developed to fabricate large-scale Si and Si1−xGex quantum dot arrays with controllable height, diameter and center-to-center distance.

Preferential synthesis and isolation of (6,5) single-wall nanotubes from one-dimensional C60 coalescence

Nanoscale ◽  
2011 ◽  
Vol 3 (10) ◽  
pp. 4190 ◽  
Author(s):  
Jinying Zhang ◽  
Yasumitsu Miyata ◽  
Ryo Kitaura ◽  
Hisanori Shinohara
Keyword(s):  
One Dimensional ◽  
Single Wall Nanotubes ◽  
Preferential Synthesis

scholarly journals Moiré Physics of One-Dimensional Related Systems and Their Measurement

2022 ◽  
Vol 2152 (1) ◽  
pp. 012035
Author(s):  
Jiaqi Zuo
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Electrical Transport ◽  
Rayleigh Scattering ◽  
Experimental Studies ◽  
Magic Angle ◽  
Sharp Drop ◽  
One Dimensional ◽  
Experimental Systems ◽  
Double Walled Carbon Nanotubes

Abstract Currently, the magic-angle graphene has given a tremendous boost to the study of unconventional superconductors. On the other hand, there were still limited experimental studies on superconductivity in one-dimensional (1D) carbon nanotube systems. The study of experimental systems in demonstrating superconductivity was therefore scientifically important. In this review, we have shown strategies toward demonstrating the superconductivity for the single double-wall carbon nanotube (DWCNT). In general, there have been two directions to analyse superconducting properties of one-dimensional materials: (i) strong correlated states (ii) anomalous electron transport operations. We introduced the transmission electron microscope (TEM) and Rayleigh scattering spectroscopy to describe the strong correlation. The theoretical foundations of moiré physics have also been described. Given all the methods, we concluded that the most intuitive way to demonstrate the superconductivity of single double-walled carbon nanotubes is the critical temperature. The sharp drop of the resistance could be directly observed, and the Tc could be obtained from the electrical transport data. In the last section, we also summarized the challenges that need to be addressed in future superconductivity studies of 1D carbon nanotubes.

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