CeNS Center for NanoScience LMU Ludwig-Maximilians-Universität München
CeNS HomepageLMU Homepage

Friday, 01 August, 2008

Visualizing the local optical response of semiconducting carbon nanotubes to DNA-wrapping

H. Qian, P. T. Araujo, C. Georgi, T. Gokus, N. Hartmann, A. A. Green, A. Jorio, M. C. Hersam, L. Novotny, and A. Hartschuh -
Nano Lett., 8 (9), 2706 (2008)

We studied the local optical response of semiconducting single-walled carbon nanotubes to wrapping by DNA segments using high resolution tip-enhanced near-field microscopy. Photoluminescence (PL) near-field images of single nanotubes reveal large DNA-wrapping-induced red shifts of the exciton energy that are two times higher than indicated by spatially averaging confocal microscopy. Near-field PL spectra taken along nanotubes feature two distinct PL bands resulting from DNA-wrapped and unwrapped nanotube segments. The transition between the two energy levels occurs on a length scale smaller than our spatial resolution of about 15 nm.



Article on journal's website