D. C. Thakur | Searcharxiv

arXiv2024

Phase separation in a binary mixture of sticky spheres

We numerically investigate the dependence of range of attractive potential on the phase separation of 2-D binary systems. Through extensive simulations and analysis, we show that when the range of attractive interactions approaches the sticky sphere limit, the system undergoes a phase separation at lower temperature. Further reduction in temperature causes the system to mix again. These mixing-demixing-mixing transitions are of first order. Such phase separation is not observed for systems with larger interaction range. In the phase separated region of the phase diagram, one of the components of the mixture chooses to be in crystalline configuration, while other being in disordered state

physics.comp-ph↗

arXiv2023

Relation between local density and density relaxation near glass transition in a glass forming binary mixture

Many investigations shed light on various correlations between structure and dynamics in supercooled liquids; however, a general relation between structure and dynamics remains elusive. This molecular dynamics simulation study identifies the interrelationship between the growth of the highest peak of the radial distribution function, variation in the radial force from this peak, and the slowdown of the density relaxation in the supercooled states of a model binary glass former. From the microscopic string-like motion in supercooled liquids, we argue that the surface density on a spherical shell around a reference particle at the highest peak of the radial distribution function can represent the free volume available for motion. We further show from these arguments and simulations that density relaxtion time and local density are connected; in this expression, the dynamics diverge at a higher critical value of local density. This relation is similar to the Vogel Fulcher Tammann relation in supercooled liquids, thus giving insight into the structural origin of the VFT as the jamming of particles in a channel of density relaxation.

cond-mat.soft↗