We demonstrate that an achiral stretching force transforms disk-shaped colloidal membranes composed of chiral rods into twisted ribbons with handedness opposite the preferred twist of the rods. Using an experimental technique that enforces torque-free boundary conditions we simultaneously measure the force-extension curve and the ribbon shape. An effective theory that accounts for the membrane bending energy and uses geometric properties of the edge to model the internal liquid crystalline degrees of freedom explains both the measured force-extension curve and the force-induced twisted shape.

中文翻译：

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力诱导的手性扭曲带的形成。

我们证明，非手性拉伸力将由手性棒组成的盘状胶体膜转变为扭曲的带，其螺旋性与棒的优选扭曲相反。使用强制实施无扭矩边界条件的实验技术，我们可以同时测量力-延伸曲线和带状形状。一个有效的理论考虑了膜的弯曲能量，并利用边缘的几何特性对内部液晶自由度建模，从而解释了测得的力-延伸曲线和力诱导的扭曲形状。