We consider an elastic helical medium formed by uniformly rotating a triclinic crystal around a given axis to constitute a helical medium giving rise to an inhomogeneous material whose tensor stiffness rotates uniformly and varies along the helix axis. A detailed analysis of its elastic properties has been done previously. Here, we are concerned in analyzing the role of thermal coupling with heat flow through the dilatation tensor. Starting from a general dynamic description of the thermoelastic phenomena which takes into account the finite speed of propagation of thermal waves, we establish a set of equations for the strains, stresses, temperature and heat flow. These equations allow to calculate the band structure and the logarithmic ratio between longitudinal and transverse strains. We express our results for different values of the thermoelastic coupling and period of the helix which show remarkable modifications when compared with the case in which no thermoelastic coupling is present.

中文翻译：

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螺旋介质弹性带结构对热膨胀的依赖性

我们考虑通过围绕给定轴均匀旋转三斜晶体形成的弹性螺旋介质来构成螺旋介质，从而产生不均匀材料，其张量刚度均匀旋转并沿螺旋轴变化。之前已经对其弹性特性进行了详细分析。在这里，我们关注的是分析热耦合与通过膨胀张量的热流的作用。从考虑热波有限传播速度的热弹性现象的一般动力学描述开始，我们建立了一组应变、应力、温度和热流方程。这些方程允许计算能带结构和纵向和横向应变之间的对数比。