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Anelastic response of the solid at ρ = 0.99. A few strained configurations (ε = 0.016,0.028,0.036,0.048,0.060,0.064) are quenched suddenly to zero strain by rescaling the atomic coordinatesto study the relaxation of stress σ(t) over time t. The stress responds by first decreasing rapidly to a negative value whose magnitude increases with the initial ε and then slowly relaxing to zero from below. For the minimally strained solid, the relaxation is essentially exponential. If the initial strain is around ε*, the dynamical response shows a second relaxation which is complex and non-monotonic. The inset shows the dependence of the average stress σa during the relaxation process on the value of the initial ε before σ(t) decreases to 0. While σa grows linearly for small ε, its growth becomes rapid as ε crosses ε*.
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A crystalline solid exhibits thermally induced localised {\em non-affine}
droplets in the absence of external stress. Here we show that upon an imposed
shear, the size of these droplets grow until they percolate at a critical
strain, well {\em below} the value at which the solid begins to yield. This
critical point does not manifest in bulk thermod...
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Citations
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Certain localised displacement fluctuations in the planar honeycomb lattice
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spatio-temporal distributions, for a lattice with harmonic nearest neighbour
and next near neighbour bonds. As the solid is destabilised by tuning
interactions, the precursor fluctuations diverge and correlations become
long-lived and long-ranged.
