Controlled production and electrical characterization of defects in carbon nanotubes Brett Goldsmith Collins Group Department of Physics and Astronomy

Production of Defects (functionalization) 1.Electrochemical defect creation 2.I(V) of nanotubes with an added defect 3.Field sensitivity of a created defect 4.Local resistance of a created defect 5.Enhancement of Chemical reactivity

1. Electrochemical Setup electrochemistry in acidic solution monitor current through the nanotube during electrochemistry PMMA Source Drain Mannik et al. PRL (2006) Goldsmith el al. Science (2007)

2. I(V) of Created Defects created defects show tunneling behavior

Tunneling?

Thermally Assisted Tunneling Mannik et al. PRL (2006)

3. Localized Field Sensitivity - SGM Record current through the nanotube circuit while scanning with a gate probe. Measures local field sensitivity Shows where the device is gate sensitive Source V SD V tip Drain VFVF a normal nanotube nanotube with a created defect

4. Local Resistance - KFM Records forces between tip and sample Measures Surface Potential Allows indirect measurement of local resistance Source V SD V tip Drain VFVF Source KFM image of a normal nanotube A nanotube with a created defect Scanned Gate image KFM image

5. Chemical reactivity of Produced Defects PMMA Pd Goldsmith el al. Science (2007)

Summary Dr. Phil Collins Brett Goldsmith Alex Kane Bucky Khalap Steve Hunt Danny Wan ACS-PRF 1.Electrochemical functionalization 2.Thermally assisted tunneling 3.Field sensitivity of created defect 4.Local resistance of created defect 5.Chemical reactivity of created defects