一维均匀Morse晶格体系的热流棘齿效应

本文系统研究了系统两端无平均温差时一维均匀Morse晶格中的热流棘齿效应. Morse晶格的两端分别与两个热浴相接触, 其中一端热浴温度周期调制,另一端热浴温度保持不变, 两端热浴温度长时平均相等. 数值结果表明, 当对一端热浴温度进行周期调制时, 系统中便会有稳定的定向热流产生. 通过改变调制频率和强度, 可以控制热流的大小及方向. 在合适的频率范围内, 可观察到一种非常有趣的现象——非定态负热导现象, 即系统中产生的定向热流逆着系统温度梯度方向由低温端流向高温端. 通过热波动力学分析(分析热流及温度分

Ratcheting thermal conduction in one-dimensional homogeneous Morse lattice systems

The ratchet effect in heat conductions of one-dimensional Morse lattices is studied when the system is located between two averagely isothermal reserviors, of which one keeps the temperature constant and the other is periodically modulated in temperature,and their temperatures averaged over a long time are equal to each other. Unidirectional heat current can be observed when one of the heat baths is periodically modulated in temperature. The efficiency and the direction of heat conduction can be rectified and controlled by adjusting the frequency and the amplitude of the modulation. An interesting non-stationary negative thermal conductivity, i.e., a reversed heat flow against the temperature gradient, is found in an appropriate region of frequency of the modulation. A heat wave scheme in revealing the spatiotemporal behavior of the heat conduction is proposed to study the this phenomenon. The influence of the parameters of the Morse lattice on the directional heat current is investigated, and so this provides theoretical support for practical applications.