Design rules for interfacial thermal conductance: Building better bridges
Design rules for interfacial thermal conductance: Building better bridges
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DOI：
10.1103/physrevb.95.195303
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发表时间：
2017-05-03
影响因子：
3.7
通讯作者：
Ghosh, Avik W.
中科院分区：
文献类型：
--
作者：
Polanco, Carlos A.;Rastgarkafshgarkolaei, Rouzbeh;Ghosh, Avik W.
我们研究了当中间匹配层的组成不同时，固-固界面上的导热系数。在没有声子-声子相互作用的情况下，附加层可以使界面电导增加或减少，这取决于(1)由于接触之间更好的桥接而增加的声子透过率和(2)必须保持其横向于界面的动量的可用传导通道的数量的减少。当包括声子-声子相互作用时，当接触层边界的电阻减小补偿附加层电阻时，附加层被认为有助于电导。对于本工作中所研究的特殊系统，当层质量接近接触质量的几何平均值时，出现最大电导。这一令人惊讶的结果通常与相干减反射膜有关，其原因是边界电阻随着界面质量比的单调增加。这种几何平均条件很容易扩展到具有指数变化质量的成分梯度界面层，从而产生宽带阻抗匹配网络的热等效值。
We study the thermal conductance across solid-solid interfaces as the composition of an intermediate matching layer is varied. In the absence of phonon-phonon interactions, an added layer can make the interfacial conductance increase or decrease depending on the interplay between (1) an increase in phonon transmission due to better bridging between the contacts and (2) a decrease in the number of available conduction channels that must conserve their momenta transverse to the interface. When phonon-phonon interactions are included, the added layer is seen to aid conductance when the decrease in resistances at the contact-layer boundaries compensate for the additional layer resistance. For the particular systems explored in this work, the maximum conductance happens when the layer mass is close to the geometric mean of the contact masses. The surprising result, usually associated with coherent antireflection coatings, follows from a monotonic increase in the boundary resistance with the interface mass ratio. This geometric mean condition readily extends to a compositionally graded interfacial layer with an exponentially varying mass that generates the thermal equivalent of a broadband impedance matching network.