Christophe Goze

ELASTIC PROPERTIES OF C AND BX CY NZ COMPOSITE NANOTUBES

We present a comparative study of the energetic, structural, and elastic properties of carbon and composite single-wall nanotubes, including BN,

Mechanical and electronic properties of carbon and boron-nitride nanotubes

{\mathrm{BC}}_{3}

SINGLE-WALL CARBON NANOTUBES FOR OPTICAL LIMITING

, and

Purification procedure of carbon nanotubes

{\mathrm{BC}}_{2}\mathrm{N}

Optical limiting properties of singlewall carbon nanotubes

nanotubes, using a nonorthogonal tight-binding formalism. Our calculations predict that carbon nanotubes have a higher Young modulus than any of the studied composite nanotubes, and of the same order as that found for defect-free graphene sheets. We obtain good agreement with the available experimental results.

Tight-binding calculation of the elastic properties of single-wall nanotubes

Abstract In this contribution we provide an overview of our recent work on the mechanical and electronic properties of carbon and boron–nitride (BN) nanotubes, which are of key relevance to practical applications and to our present understanding of low-dimensional structures. On the mechanical properties we look at the nanotube axial stiffness, bending and torsion dynamics. We found that chiral tubes exhibit an interesting asymmetric torsional behaviour with respect to left and right twist that is absent in armchair or zig-zag tubes. Topological defects are seen to modify slightly the mechanical response of the carbon network under applied strain. On the electronic properties we present an analysis of the role of the environment in nanotube density of states relevant for scanning tunneling spectroscopy (STS). Finally we present results on the electronic density of states for BN nanotubes that can be used as a complementary fingerprint of those structures in STS experiments and for their applications in composite (C–BN) electronic devices.

Elastic Properties of Single-Wall Nanotubes

Abstract We report on the non-linear optical transmittance of single-wall carbon nanotubes (SWNT) in a water/surfactant suspension. Optical limiting is observed at low-energy thresholds both in the visible and near-infrared. We find small non-linear thresholds and large optical densities that match or overpass the performances of other good optical limiters (C60 and carbon black) both in the visible and in the near-infrared, which makes SWNT very promising systems for broadband optical limiting.

Photoactivated method and device for broadband limitation of a luminous flux

We report results on purification and characterization of single wall carbon nanotubes prepared by the electric arc method. The process consists of a chemical treatment based on a reflux with nitric acid followed by successive filtration steps (tangential flow and frontal filtration) of a suspension of the raw material. The effects of each step are analysed by SEM and TEM.

High resolution NMR studies of one and two dimensional polymerized C60

We report on the optical limiting performances of singlewall carbon nanotubes. The nonlinear transmission of the samples is investigated using nanosecond Nd:YAG laser pulses at 532 nm and 1064 nm. Z-scan experiments are carried out at different incident energies in order to identify the effects responsible for nonlinear transmission. We find that nonlinear scattering and nonlinear refraction are the dominant mechanisms. Optical limiting efficiencies are compared with those of multiwall nanotubes, carbon black suspensions and fullerenes.

Purification des nanotubes de carbone monofeuillets

We report theoretical predictions of the energetic, structural and elastic properties of single wall nanotubes. We shall discuss estimations of the Poisson ratio and Young modulus for C, BN, BC3 and BC2N nanotubes. We have focused attention on both arm-chair (n,n) and zig-zag (n,0) nanotubes, with n in the range 5 to 20. For the particular case of C nanotubes we have also considered a number of chiral examples. A brief outline of the theoretical methods will be given, followed by a discussion of the results obtained, paying particular attention to the elastic properties.