Haze and Polarization Scrambling of Nonlinearly Scattered Light From Antiglare Si Nanorod Surface

The scattering angle, the Haze ratio, and the field polarization factor of the frequency-doubled Nd:YAG laser nonlinearly scattered from the semiconductor nanorod surface are investigated. Both the scattering angle and the reflected Haze ratio of the laser beam reflected from Si nanorod surface present a nonlinearly increasing trend with nanorod length. As the nanorod lengthens from 190 to 2760 nm, the scattering angle broadens from 2.5° to 25° and from 2.5° to 24°. Concurrently, the reflected Haze ratio increases from 5% to 22% and 3% to 21% under TE and TM-mode incidences, respectively. A significant polarization scrambling transfers the linearly polarization into an elliptical polarization, and the field polarization factor increases from 0.54 to 0.86 and from 0.42 to 0.84 under TE- and TM-mode incidences with an enlarging nanorod length from 190 to 2760 nm. The reflected Haze ratio is linearly proportional with the broadened scattering angle. However, the field polarization factor shows a gradually saturating effect at larger scattering angle. The theoretical calculation is used to quantitatively analyze the polarization scrambling effect, which demonstrates that the scattered wave nonlinearly depends on the surface corrugation and can be expressed by the second-order function of the surface corrugation strength. The strong correlations of the TE-mode scattering with the nanorod length and the TM-mode scattering with the laser incident angle are observed. The polarization of the reflected laser beam eventually transfers from a linear to an elliptical one with a nanorod length exceeding over 1 μm.