Executive Summary : | The proposed project aims to confirm the discovery of critical singularities in thermally-induced hysteretic abrupt phase transitions in transition metal oxides (V₂O₃ and NdNi0₃). The study has observed dynamic scaling, critical slowing down, and critical opalescence, which are unexpected for any abrupt phase transition. Spinodal singularities, inflection points in the free energy, control hysteretic transitions under deep supersaturation conditions. These spinodals are inflection points in the free energy, marking the transition from metastable to unstable phase as a function of temperature or field. The project aims to critically examine this argument and provide empirical elaborations, especially under non-ideal conditions of finite temperature and finite disorder. The funding is primarily to make the team partially self-sufficient in sample growth via pulsed laser deposition and set up a new home-built liquid nitrogen-based apparatus for these investigations. Many other materials undergoing structural phase transitions, such as martensites, Heusler alloys, halide perovskites, spin-crossover materials, and charge-density-wave compounds, are expected to show similar behavior. The project proposes a combined and simultaneous study of optical and transport characteristics under precisely controlled conditions, focusing on light scattering and analyzing speckle patterns at the transition. The aim is to critically examine the existence and attributes of the abrupt phase transitions in the mean field universality class, which is relevant to a large number of well-studied solid state systems. |