Unzipping DNA by a periodic force: Hysteresis loops, Dynamical order parameter, Correlations and Equilibrium curves

M. Suman Kalyan; Rajeev Kapri

doi:10.1063/1.5081099

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arXiv · 1811.08082

Unzipping DNA by a periodic force: Hysteresis loops, Dynamical order parameter, Correlations and Equilibrium curves

M. Suman Kalyan·Rajeev Kapri

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Abstract

The unzipping of a double stranded DNA whose ends are subjected to a time dependent periodic force with frequency $ω$ and amplitude $G$ is studied using Monte Carlo simulations. We obtain the dynamical order parameter, $Q$, defined as the time average extension between the end monomers of two strands of the DNA over a period, and its probability distributions $P(Q)$ at various force amplitudes and frequencies. We also study the time autocorrelations of extension and the dynamical order parameter for various chain lengths. The equilibrium force-distance isotherms were also obtained at various frequencies by using non-equilibrium work measurements.

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M. Suman Kalyan, Rajeev Kapri. 2019-06-14. Unzipping DNA by a periodic force: Hysteresis loops, Dynamical order parameter, Correlations and Equilibrium curves. https://doi.org/10.1063/1.5081099

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