The lattice thermal conductivity (LTC) of silicon nanowires (NWs) with diameters of 115, 56, 37 and 22 nm in the temperature range of 2–300 K for different pressures ranging from 0 to 10 GPa, was calculated by employing a modified Callaway model. Both longitudinal and transverse modes were explicitly considered within the model. A strategy is utilized to calculate the Debye and phonon group velocity in addition to the bulk modulus and it is derivative for different NW diameters from their related melting temperature under different pressures. The influence of the Gruneisen parameter, surface roughness and dislocation as structurally dependent parameters are successfully exploited to correlate the calculated values of LTC to that of the experimentally measured curves at various pressures including zero. The respective application of the Murnghan and Clapeyron equations for pressure-dependent lattice volume and melting temperature in the Callaway model produces results that tend to be systematically applicable by this model. The confinement and size effects of phonons and the role of pressure in the reduction of LTC are investigated. The peak value of LTC decreases with the increase of pressure for both bulk and its nanowires.

直径为 115、56、37 和 22 nm 的硅纳米线 (NW) 在 2–300 K 的温度范围内，在 0 到 10 GPa 的不同压力范围内的晶格热导率 (LTC) 是通过使用改进的 Callaway 计算的模型。模型中明确考虑了纵向和横向模式。除了体积模量之外，还使用一种策略来计算德拜和声子群速度，并且它是不同 NW 直径在不同压力下的相关熔化温度的导数。成功地利用 Gruneisen 参数、表面粗糙度和位错作为结构相关参数的影响，将 LTC 的计算值与包括零在内的各种压力下的实验测量曲线的值相关联。在 Callaway 模型中分别应用 Murnghan 和 Clapeyron 方程与压力相关的晶格体积和熔化温度产生的结果倾向于系统地适用于该模型。研究了声子的限制和尺寸效应以及压力在降低 LTC 中的作用。LTC 的峰值随着体块及其纳米线压力的增加而减小。