Competing spring constant versus double resonance effects on the properties of dispersive modes in isolated single-wall carbon nanotubes

A. G. Souza Filho,* A. Jorio, Ge. G. Samsonidze, G. Dresselhaus, M. A. Pimenta, M. S. Dresselhaus Anna K. Swan, M. S. Ünlü, B. B. Goldberg and R. Saito Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 Departamento de Fı́sica, Universidade Federal do Ceará, Fortaleza-CE, 60455-760, Brazil Departamento de Fı́sica, Universidade Federal de Minas Gerais, Belo Horizonte–MG, 30123-970 Brazil Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307 Electrical and Computer Engineering Department, Boston University, Boston, Massachusetts 02215 Department of Physics, Boston University, Boston, Massachusetts 02215 Department of Electronic-Engineering, University of Electro-Communications and CREST-JST, Tokyo, 182-8585, Japan ~Received 2 July 2002; revised manuscript received 16 September 2002; published 31 January 2003!