Report
Shear-strain and shear-stress fluctuations in generalized Gaussian ensemble simulations of isotropic elastic networks
| العنوان: | Shear-strain and shear-stress fluctuations in generalized Gaussian ensemble simulations of isotropic elastic networks |
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| المؤلفون: | Wittmer, J. P., Kriuchevskyi, I., Baschnagel, J., Xu, H. |
| سنة النشر: | 2015 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Statistical Mechanics |
| الوصف: | Shear-strain and shear-stress correlations in isotropic elastic bodies are investigated both theoretically and numerically at either imposed mean shear-stress $\tau$ ($\lambda=0$) or shear-strain $\gamma$ ($\lambda=1$) and for more general values of a dimensionless parameter $\lambda$ characterizing the generalized Gaussian ensemble. It allows to tune the strain fluctuations $\mu_{\gamma\gamma} \equiv \beta V \la \delta \gamma^2 \ra = (1-\lambda)/G_{eq}$ with $\beta$ being the inverse temperature, $V$ the volume, $\gamma$ the instantaneous strain and $G_{eq}$ the equilibrium shear modulus. Focusing on spring networks in two dimensions we show, e.g., for the stress fluctuations $\mu_{\tau\tau} \equiv \beta V \la \delta\tau^2 \ra$ ($\tau$ being the instantaneous stress) that $\mu_{\tau\tau} = \mu_{A} - \lambda G_{eq}$ with $\mu_{A} = \mu_{\tau\tau}|_{\lambda=0}$ being the affine shear-elasticity. For the stress autocorrelation function $c_{\tau\tau}(t) \equiv \beta V \la \delta \tau(t) \delta \tau(0) \ra$ this result is then seen (assuming a sufficiently slow shear-stress barostat) to generalize to $c_{\tau\tau}(t) = G(t) - \lambda \Geq$ with $G(t)$ being the shear-stress relaxation modulus. Comment: 17 pages, 15 figures |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1140/epjb/e2015-60506-6 |
| URL الوصول: | http://arxiv.org/abs/1508.03726 |
| رقم الانضمام: | edsarx.1508.03726 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1140/epjb/e2015-60506-6 |
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