论文标题
SI/SIO $ _2 $ MULTISHELL纳米管中的声子和热传输：原子研究
Phonons and thermal transport in Si/SiO$_2$ multishell nanotubes: Atomistic study
论文作者
论文摘要
理论上研究了Si/Sio $ _2 $ Multishell纳米管中的热传输。使用原子晶格动力学方法获得了声子能谱。在松弛时间近似中使用玻尔兹曼传输方程计算导热率。与均匀的SI纳米线相比，多壳纳米管中振动光谱的重新分布会导致声子速度和热导率的降低。 Si/Sio $ _2 $接口上的声子散射是这些结构中热导率强烈降低（在室温下降至0.2 w/mk）的另一个关键因素。我们证明，可以通过适当选择纳米管的几何参数来有效地抑制Si/Sio $ _2 $纳米管中的声子热传输：侧面横截面，厚度和壳数量。
Thermal transport in the Si/SiO$_2$ multishell nanotubes is investigated theoretically. The phonon energy spectra are obtained using the atomistic Lattice Dynamics approach. Thermal conductivity is calculated using the Boltzmann transport equation within the relaxation time approximation. Redistribution of the vibrational spectra in multishell nanotubes leads to a decrease of the phonon group velocity and the thermal conductivity as compared to homogeneous Si nanowires. Phonon scattering on the Si/SiO$_2$ interfaces is another key factor of strong reduction of the thermal conductivity in these structures (down to 0.2 W/mK at room temperature). We demonstrate that phonon thermal transport in Si/SiO$_2$ nanotubes can be efficiently suppressed by a proper choice of nanotube's geometrical parameters: lateral cross-section, thickness and number of shells.
