Interplay between phonon confinement and Fano effect on Raman line shape for semiconductor nanostructures: Analytical study

• It is very important to study the multiple physical phenomenon happing at nanoscale.
• Both Quantum confinement effect and Fano effect attribute asymmetric Raman line shape.
• Here we have given an analytical description to study the both effect individually and jointly.

Theoretical Raman line shape functions have been studied to take care of quantum confinement effect and Fano effect individually and jointly. The characteristics of various Raman line shapes have been studied in terms of the broadening and asymmetry of Raman line shapes. It is shown that the asymmetry in the Raman line-shape function caused by these two effects individually does not add linearly to give asymmetry of line-shape generated by considering the combined effect. This indicates existence of interplay between the two effects. The origin of interplay lies in the fact that Fano effect itself depends on quantum confinement effect and in turn provides an asymmetry. This can not be explained by considering the two effects contribution independent of each other.