Free energy and segregation dynamics of two channel-confined polymers of different lengths

Polymers confined to a narrow channel are subject strong entropic forces that tend drive the molecules apart. In this study, we use Monte Carlo computer simulations study segregation behavior of two flexible hard-sphere polymers under confinement in cylindrical channel. We focus on effects using different lengths. measure variation conformational free energy, $F$, with center-of-mass separation distance, $\lambda$. The reveal four regimes, characterized by scaling properties energy respect polymer lengths and diameter, $D$. propose regime map which state system is determined values quantities $N_2/N_1$ $\lambda/(N_1+N_2)D^{-\beta}$, where $N_1$ $N_2$ lengths, $\beta\approx 0.64$. observed $F(\lambda)$ each reasonable agreement predictions simple theoretical model. addition, MC dynamics initially overlapping measurement incremental mean first-passage time For systems wide range $\lambda$ short nested within longer one, close expected for noninteracting 1D random walkers undergoing unbiased diffusion. When gradient large rapid out-of-equilibrium effects.