Nonlinear Fano-Raman line-shape evolution: direct evidence of the creation and annihilation of interferons in V2O5

Abstract

A non-linear temperature-dependent Fano resonance in V2O5 micro-crystallites is discovered, which also is found to be dictated by the laser flux. A Gaussian temperature-dependent Fano parameter is observed and explained through an interferon creation/annihilation mechanism from/to phonons which was found to be a thermodynamically favorable process. Systematic temperature- and power-dependent Raman studies explain the electron-phonon interaction in V2O5 under resonant excitation. The non-linear dynamics of interferon (electron-phonon coupling state) formation with temperature are explained and an empirical relationship has been formulated to identify the temperature at which the interferon population is maximum, beyond which interferons get annihilated. © 2025 The Royal Society of Chemistry.