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Updated: Jun 21, 2025

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Shedding light on evolution of Raman line shape with probing laser power: Light-induced perturbation in
Omkar V Rambadey1, Kailash Kumar1, Ritu Nain1
1Materials Research Laboratory, Department of Physics, Indian Institute of Technology Indore, Simrol, Khandwa Road, Indore 453552, India.
Abstract:
The laser power mediated changes in the Raman line shape have been considered in terms of interference between discrete phonon states ρ and the electronic continuum states ϰ contributed by Urbach tail states. The laser-induced effects are treated in terms of the increase in the surface temperature and thereby the scaling of electronic disorder, i.e., Urbach energy, which can further contribute to the electron-phonon interactions. Therefore, the visualization of this effect is attempted analytically as a perturbation term in the Hamiltonian, which clearly accounts for the observed changes with laser power. This has been investigated based on the experimental results of laser power dependent Raman spectra of bulk EuFeO3 and silicon nanowires, which are found to provide convincing interpretations.
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