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arXiv · 2207.11140

Study of unzipping transitions in an adsorbed polymer by a periodic force

Ramu Kumar Yadav
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Abstract

Using Monte Carlo simulations, we study the dynamic transitions in the unzipping of an adsorbed homogeneous polymer on a surface (or wall). We consider three different types of surfaces. One end of the polymer is always kept anchored, and other end monomer is subjected to a periodic force with frequency $\omega$ and amplitude $g_0$. We observe that the force-distance isotherms show hysteresis loops in all the three cases. For all the three cases, it is found that the area of the hysteresis loop, $A_{loop}$, scales as $1/\omega$ in the higher frequency regime, and as $g_0^{\alpha} \omega^{\beta}$ with exponents $\alpha = 1$ and $\beta = 1.25$ in the lower frequency regime. The values of exponents $\alpha$ and $\beta$ are similar to the exponents obtained in the earlier Monte Carlo simulation studies of DNA chains and a Langevin dynamics simulation study of longer DNA chains.

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Ramu Kumar Yadav. 2022-07-22. Study of unzipping transitions in an adsorbed polymer by a periodic force. https://arxiv.org/abs/2207.11140

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