The group is interested in a range of topics from very fundamental studies of the interaction of femtosecond laser pulses with complex molecules and clusters to the study of chemical vapour deposition growth of carbon nanotubes and their properties and potential applications. The fundamental gas phase fs studies provide information on the complex intramolecular energy coupling timescales and mechanisms in systems with a large but finite number of degrees of freedom. Recently we have looked at the process of intracluster molecular fusion of fullerenes [3] that can occur when clusters of fullerenes are highly excited on a sub ps timescale. We are developing a photoelectron imaging spectrometer that will be used to study the time-, energy- and emission angle-dependence of photoelectrons produced from complex molecules and clusters excited by ultrashort laser pulses.

The nanotube activities involve the study of carbon nanotube growth using a variety of chemical vapour deposition techniques and in situ spectroscopy methods. The main aim is to develop a means of controlling the chirality of nanotubes (and thus the electronic properties) at the growth stage. We have recently developed a technique for growing nanotubes at low ambient temperature [4] that provides a means for directly growing nanotube devices on CMOS chips and other substrates that are unable to withstand the high temperatures normally required for growing high quality nanotube material. In addition, we are exploring the nanoelectromechanical properties of carbon nanotubes [1] and, together with international collaborators (from Russia, South Korea and Sweden), e.g. [2], we are working on fabricating and characterising nanoelectronic, nanoelectromechanical and photonic devices based on nanotubes and vertically aligned carbon nanofibres.

Photo of the PEI Spectrometer screen when ionising Xe atoms with intense fs laser pulses, showing ATI structure	In situ Raman measurement of influence of strain on properties of an individual SWNT

SELECTED RECENT PUBLICATIONS

1. In situ Raman Measurements of Suspended Individual Single-Walled Carbon Nanotubes under Strain; S.W. Lee, G.-H. Jeong, E.E.B. Campbell, Nano Letters 2007, in press
2. Carbon Nanotube Bolometers; M. Tarasov, J. Svensson, L. Kuzmin, E.E.B. Campbell, Appl. Phys. Lett. 2007 90 163503
3. Molecular Fusion within Fullerene Clusters induced by Femtosecond Laser Excitation; M. Heden, M. Kjellberg, A.V. Bulgakov, K. Hansen, E.E.B. Campbel, Euro. Phys. J. D. 2007 43 255-259
4. Low Ambient Temperature CVD Growth of Carbon Nanotubes; S. Dittmer, O.A. Nerushev, E.E.B. Campbell, Appl. Phys. A. 2006 84 243-246
5. Surface Entropy of Rare Gas Clusters; S. Prasalovich, K. Hansen, M. Kjellberg, V.N. Popok, E.E.B. Campbell, J. Chem. Phys. 2005 123 084317