Lerner Edan, DeGiuli Eric, Düring Gustavo, Wyart Matthieu
New York University, Center for Soft Matter Research, 4 Washington Place, New York, NY 10003, USA.
Soft Matter. 2014 Jul 28;10(28):5085-92. doi: 10.1039/c4sm00311j.
We show numerically that the response of simple amorphous solids (elastic networks and particle packings) to a local force dipole is characterized by a lengthscale lc that diverges as unjamming is approached as lc ∼ (z - 2d)(-1/2), where z ≥ 2d is the mean coordination, and d is the spatial dimension, at odds with previous numerical claims. We also show how the magnitude of the lengthscale lc is amplified by the presence of internal stresses in the disordered solid. Our data suggests a divergence of lc ∼ (pc - p)(-1/4) with proximity to a critical internal stress pc at which soft elastic modes become unstable.
我们通过数值计算表明，简单非晶态固体（弹性网络和颗粒堆积）对局部力偶极子的响应具有一个长度尺度(lc)，当接近非堵塞状态时，(lc)会发散，其关系为(lc ∼ (z - 2d)(-1/2))，其中(z ≥ 2d)是平均配位数，(d)是空间维度，这与之前的数值结果不同。我们还展示了无序固体中内应力的存在如何放大长度尺度(lc)的大小。我们的数据表明，随着接近临界内应力(pc)，(lc)会以(lc ∼ (pc - p)(-1/4))的形式发散，此时软弹性模式变得不稳定。
