Material properties dependent on the thermal transport in a cylindrical nanowire**Project supported by the National Natural Science Foundation of China (Grant No. 11404110), the Natural Science Foundation of Hunan Province, China (Grant Nos. 14JJ3139, 2015JJ6027, and 2015JJ6030), the Outstanding Young Program from the Education Department of Hunan Province, China (Grant No. 14B046), and the Doctoral Activation Foundation of Hunan Institute

Abstract

Using the elastic wave continuum model, we investigate the effect of material properties on ballistic thermal transport in a cylindrical nanowire. A comparative analysis for the convexity-shaped and concavity-shaped structure is made. It is found that in the convexity-shaped structure, the material with higher wave velocity in the convexity region can increase the thermal conductance at the lower temperature range; the thermal conductance of the nanowire with higher wave velocity in the convexity region is lower than that of the nanowire with lower wave velocity in the convexity region at the higher temperature range. However, in the concavity-shaped structure, the material properties of the concavity region have less effect on the thermal conductance at the lower temperature range; the material with higher wave velocity in the concavity region can reduce the thermal conductance at the higher temperature range. A brief analysis of these results is given.