Modeling the relaxation and crystallization kinetics of glass without fictive temperature: Toy landscape approach

Relaxation and crystallization are key kinetic processes that must be understood to build a comprehensive understanding of the supercooled liquid and glassy states. Traditional approaches have been unable to capture the underlying physics accurately due to assumptions about phenomenological order parameters such as fictive temperature. In this work, we show that glass relaxation can be accurately modeled through a simplified “toy” enthalpy landscape approach, bypassing the use of fictive temperature. Moreover, the same simplified enthalpy landscape provides insights into the thermodynamics and kinetics of crystallization. The toy landscape approach recovers key predictions from the traditional fictive temperature description, but it is based on a more accurate physical framework, giving fundamental knowledge of the glass relaxation and crystallization processes.