Distinguishing Field Effects from Charge Effects in the Optoelectronic Properties of Carbon Nanotube Films

Figure 3

Raman spectra for pure SWNT film (lower) and SWNT-PVA composite (upper) obtained with 785 nm excitation. The two spectra are offset for clarity. No noticeable frequency shifts are observed. The inset shows the RBM modes obtained for 514 nm (bottom), 633 nm (middle), and 785 nm (upper) excitations, used to determine the diameters present in our samples.