Optical nonlinearity in nanostructured carbon thin films fabricated by pulsed laser deposition technique

In the present paper, the measurement of nonlinear refractive index coefficient in nanostructured carbon thin films deposited via pulsed laser deposition (PLD) technique is reported. The PLD carbon thin films were characterized by micro-Raman spectroscopy and ellipsometry. Raman spectra showed characteristic D and G band around ~ 1350 cm− 1 and ~ 1580 cm− 1 respectively. The nonlinear refractive index of the carbon films was measured by closed aperture Z-scan technique using He-Ne laser. The nonlinear refractive index coefficient of carbon thin films was found to increase from (6.08 ± 0.75) × 10− 4 cm2/W to (1.69 ± 0.13) × 10− 3 cm2/W with the deposition temperature from room temperature to 750 °C, respectively.