Writhe distribution of stretched polymers

Motivated by experiments in which single deoxyribose nucleic acid molecules are stretched and twisted we consider a perturbative approach around very high forces, where we determine the writhe distribution in a simple, analytically tractable model. Our results are in agreement with recent simulations and experiments.

Figure 1

The writhe distribution $P\left(W\right)$ for $f=2$ and $f=5$ (dashed curve) for $L∕L_{\mathrm{BP}}=10$.