Laser absorption scanning tunneling microscopy of carbon nanotubes.
We report single molecule laser absorption by carbon nanotubes stamped under ultrahigh vacuum onto Si(100)2x1:H surfaces. Absorption is detected by scanning tunneling microscopy. Images are obtained with and without modulated laser excitation using lock-in amplification and a rear-illumination geometry to reduce thermal effects. Noise appears at topographic edges and is analyzed by a quantitative model in terms of scan speed, mechanical instabilities, and feedback current fluctuations at the edge of the nanotubes. Noise due to mechanical instabilities is shown to persist even in the limit of slow scan speed.
Ballard
Joshua B
JB
Beckman Institute of Advanced Science and Technology, Department of Chemistry, Center for Biophysics and Computational Biology, University of Illinois, Urbana, 61801, USA.
Carmichael
Erin S
ES
Shi
Dongxia
D
Lyding
Joseph W
JW
Gruebele
Martin
M