Transcritical transition of the fluid around the interface

In this letter, we provide fundamental insights into the dynamic transcritical transition process using molecular dynamics simulations. A transcritical region, which covers three different fluid states, was discovered as a substitute for the traditional interface. The physical properties, such as temperature and density, exhibited a highly non-linear distribution in the transcritical region. Meanwhile, the surface tension was found to exist throughout the transcritical region, and the magnitude was directly proportional to $ - \rho \cdot {\nabla ^2}\rho $