Non-Hookean statistical mechanics of clamped graphene ribbons
Non-Hookean statistical mechanics of clamped graphene ribbons
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DOI：
10.1103/physrevb.95.104109
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发表时间：
2017-03-22
影响因子：
3.7
通讯作者：
Sknepnek, Rastko
中科院分区：
文献类型：
--
作者：
Bowick, Mark J.;Kosmrlj, Andrej;Sknepnek, Rastko
热波动的片材和带状物提供了一个有趣的论坛，其中调查胡克定律的强烈违反：大距离弹性参数实际上不是常数，而是取决于宏观尺寸。最近的实验的启发，独立的石墨烯悬臂梁，我们联合收割机了薄弹性板的统计力学和大规模的数值模拟研究的热重整化的弯曲刚度的石墨烯带夹在一端。对于尺寸为W x L（L >= W）的带，当W < l（th）时，由悬臂变形确定的宏观弯曲刚度kappa（R）与宽度无关，其中l（th）是热长度尺度，正如预期的那样。然而，当W> l（th）时，这种热重整化的弯曲刚度开始系统地增加，与标度理论一致，尽管在我们的模拟中，我们不太能够达到确定完全发展的幂律依赖于W所需的系统尺寸。当带长L > l（p）时，其中l（p）是与W相关的热重整化带长，我们观察到标度坍缩和大尺度随机游走行为的开始。
Thermally fluctuating sheets and ribbons provide an intriguing forum in which to investigate strong violations of Hooke's Law: Large distance elastic parameters are in fact not constant but instead depend on the macroscopic dimensions. Inspired by recent experiments on free-standing graphene cantilevers, we combine the statistical mechanics of thin elastic plates and large-scale numerical simulations to investigate the thermal renormalization of the bending rigidity of graphene ribbons clamped at one end. For ribbons of dimensionsW x L (with L >= W), the macroscopic bending rigidity kappa(R) determined from cantilever deformations is independent of the width when W < l(th), where l(th) is a thermal length scale, as expected. WhenW > l(th), however, this thermally renormalized bending rigidity begins to systematically increase, in agreement with the scaling theory, although in our simulations we were not quite able to reach the system sizes necessary to determine the fully developed power law dependence on W. When the ribbon length L > l(p), where l(p) is the W-dependent thermally renormalized ribbon persistence length, we observe a scaling collapse and the beginnings of large scale random walk behavior.