【摘要】 采用非平衡分子动力学（NEMD）方法对钛酸锶薄膜在不同条件下的室温热导率进行研究，结果表明：当薄膜厚度由4.69 nm增加至10.93 nm时，钛酸锶薄膜的热导率也随之增加，数值由1.616 Wm^-1K^-1增加到1.768 Wm^-1K^-1,表现出显著的尺寸效应；厚度为6.248 nm,氧空位浓度由0.039%增加至0.195%的钛酸锶薄膜，其热导率随着氧空位浓度的增加由1.522 Wm^-1K^-1降低至1.181 Wm^-1K^-1.可以看出，钛酸锶材料的低维化以及氧缺陷能使钛酸锶薄膜的热导率降低.分析讨论了厚度和氧空位浓度对钛酸锶薄膜导热系数的影响，并与已有实验研究结果进行对比证实了本文研究的合理性与可靠性，本研究对提高热电材料钛酸锶的性能具有重要参考意义.更多还原

【Abstract】 Non-equilibrium molecular dynamics（NEMD） method was used to study the thermal conductivity of strontium titanate thin films at room temperature under different conditions.The results showed that: The thermal conductivity of strontium titanate films increased from 1.616 Wm^-1K^-1 to 1.768 Wm^-1K^-1 when the thickness of the films increased from 4.69 nm to 10.93 nm, showing a significant size effect.When the oxygen vacancy concentration increased from 0.039% to 0.195%,the thermal conductivity of strontium titanate thin films with thickness of 6.248 nm decreased from 1.522 Wm^-1K^-1 to 1.181 Wm^-1K^-1 with increasing oxygen vacancy concentration.It can be seen that the thermal conductivity of strontium titanate films can be reduced due to the low dimensionality of strontium titanate materials and oxygen defects.The influence of thickness and oxygen vacancy concentration on the thermal conductivity of strontium titanate thin films is analyzed and discussed, and the rationality and reliability of this study are verified by comparison with the existing experimental results.The study in this paper has an important reference significance for improving the performance of strontium titanate thermoelectric materials.更多还原