Position Sensitive Photothermoelectric Effect in Suspended Single-Walled Carbon Nanotube Films

The photovoltage of suspended single-walled carbon nanotube (SWNT) films were measured in high vacuum, Experiments with localized illumination showed significant photovoltage amplitudes of up to 0.36 m V at 1.2 mW intensity. The photoresponse dependence upon the laser position was explained by a thermal mechanism that is independent of the nanotube-metal depend on doping heterogeneities of the film. A model was developed to deduce from the data the spatial variation of the local Seebeck coefficient for a given photovoltage profile.