Maire Jeremie, Anufriev Roman, Hori Takuma, Shiomi Junichiro, Volz Sebastian, Nomura Masahiro
Institute of Industrial Science, The University of Tokyo, Tokyo, 153-8505, Japan.
Laboratory for Integrated Micro Mechatronic Systems/National Center for Scientific Research-Institute of Industrial Science (LIMMS/CNRS-IIS), The University of Tokyo, Tokyo, 153-8505, Japan.
Sci Rep. 2018 Mar 13;8(1):4452. doi: 10.1038/s41598-018-22509-0.
Semiconductor nanowires are potential building blocks for future thermoelectrics because of their low thermal conductivity. Recent theoretical works suggest that thermal conductivity of nanowires can be further reduced by additional constrictions, pillars or wings. Here, we experimentally study heat conduction in silicon nanowires with periodic wings, called fishbone nanowires. We find that like in pristine nanowires, the nanowire cross-section controls thermal conductivity of fishbone nanowires. However, the periodic wings further reduce the thermal conductivity. Whereas an increase in the wing width only slightly affects the thermal conductivity, an increase in the wing depth clearly reduces thermal conductivity, and this reduction is stronger in the structures with narrower nanowires. Our experimental data is supported by the Callaway-Holland model, finite element modelling and phonon transport simulations.
由于半导体纳米线的低导热性，它们是未来热电材料的潜在构建单元。最近的理论研究表明，通过额外的收缩、支柱或翼片可以进一步降低纳米线的导热性。在此，我们通过实验研究了具有周期性翼片的硅纳米线（即鱼骨状纳米线）中的热传导。我们发现，与原始纳米线一样，纳米线的横截面控制着鱼骨状纳米线的导热性。然而，周期性翼片进一步降低了导热性。翼片宽度的增加仅对导热性有轻微影响，而翼片深度的增加则明显降低了导热性，并且这种降低在纳米线较窄的结构中更为显著。我们的实验数据得到了卡洛维-霍兰德模型、有限元建模和声子输运模拟的支持。
