Heat Capacity and Thermal Conductance Calculations for Non-Metallic Crystalline Nanowires Based on Elastic Dispersion Relations

We evaluate the real dispersion relations of circular non-metallic crystalline nanowires based on elasticity equations and stress-free boundary condition. Based on the dispersion relations, the nanowire heat capacity (specific heat) and ballistic conductance are calculated as functions of temperature. Distinct dimensional dependence can be clearly seen as temperature varies. Transitional point between one-dimensional (1-D) and three-dimensional (3-D) behaviors is identified. Similar to previously reported studies on the nanotube systems, at very low temperatures and/or for very thin nanowires the specific heat capacity varies as T1/2 due to the dominance of the flexural modes.