An Investigation of SHG Response from the CNT/Peptide Interface as a Function of Variant Peptide Concentrations and Tunable Wavelengths by Using a Monochromator

The carbon nanotubes (CNT) was fabricated on the Si/SiO2/Co substrate by chemical vapor deposition (CVD) method. After that, we dropped variant concentrations of peptide molecules on the CNT surface and measured the SHG intensity from the CNT/PEP interface. We found that the SHG intensity was maximum for all concentrations of peptide molecules at 532 nm when we tuned the wavelength manually by using monochromator. At the fixed SHG wavelength, the intensity was increased with the increase of peptide concentrations. This is because of the availability of the different types of C-bonds may produce chiral structure. This chirality behavior could be the reason for the generation of SHG signal with the increase of peptides concentrations on the CNT surface.