摘要
We investigate the thermoelectric energy conversion efficiency of Si and Ge nanowires, and in particular, that of Si/Ge core-shell nanowires. We show how the presence of a thin Ge shell on a Si core nanowire increases the overall figure of merit. We find the optimal thickness of the Ge shell to provide the largest figure of merit for the devices. We also consider Ge core/Si shell nanowires, and show that an optimal thickness of the Si shell does not exist, since the figure of merit is a monotonically decreasing function of the radius of the nanowire. Finally, we verify the empirical law relating the electron energy gap to the optimal working temperature that maximizes the efficiency of the device.
我们调查 Si 和 Ge nanowires 的热电的精力变换效率,并且特别地, Si/Ge 核心壳 nanowires 的。我们显示出 Si 核心 nanowire 上的薄 Ge 壳的存在怎么增加优点的全面数字。我们发现 Ge 壳的最佳的厚度为设备提供优点的最大的数字。我们也认为 Ge core/Si 是壳 nanowires,并且证明 Si 壳的最佳的厚度不存在,自从优点的数字是 nanowire 的半径的 monotonically 减少的功能。最后,我们验证联系电子精力差距到最大化设备的效率的最佳的工作温度的实验法律。