Abstract

We have extensively studied the laser-induced Fano scattering, electron-phonon coupling, bond length and phonon lifetime of the alpha-Fe2O3 nanostructure prepared through a simple co-precipitation method. A noticeable red shift and asymmetry have been observed in the phonon modes of the prepared alpha-Fe2O3 nanostructure. The traditional assessment of asymmetric broadening and a red shift in the Raman spectra of a nanomaterial was due to the quantum confinement effect. In the present investigation, the red shift and the asymmetry in the phonon modes of the alpha-Fe2O3 nanostructure have been studied on the basis of the heating effect and Fano interference between the discrete phonon and the laser-induced electron plasma in the nanomaterial. The observed asymmetrical factors of the A(1g)(1) and E-g(4) phonon modes were positive and negative respectively and are seen to be decreasing with the laser power. The laser-induced surface temperature of the material has been studied using the Stokes/anti-Stokes method. The bond lengths of the Fe-O molecules present in the alpha-Fe2O3 nanomaterial increased and the calculated Frohlich interactions decreased with the laser energy.