论文标题
在2D材料中观察玻色子峰
Observation of the Boson Peak in a 2D Material
论文作者
论文摘要
相对于Debye模型，玻色子峰是状态的声子密度的过量，该模型的频率低于Debye极限。它存在于大多数无定形材料中，如最近所示，有时也可以在晶体中找到。在这里，我们提供了2D材料中玻色子峰的第一个实验证据，即2D二氧化硅（Sio $ _2 $）。测量是通过氦原子散射获得的。看到无散的玻色子峰为$ 6 \ pm 0.5 $ meV（1.5 $ \ pm $ 0.15 THz）和$ -6 \ pm 1.5 $ meV（$ -1.5 \ pm 0.4 $ thz），有合理的证据，有双重激发，$ \ pm 12 \ pm 12 \ pm 2.5 $ 2.5 $ 2.5 $ 2.5 $ 2.9 \ pm 0.6 $ thz）。
The boson peak is an excess in the phonon density of states relative to the Debye Model, which occurs at frequencies below the Debye limit. It is present in most amorphous materials and, as was recently shown, can sometimes be found also in crystals. Here we present first experimental evidence of the boson peak in a 2D material, namely 2D silica (SiO$_2$). The measurements were obtained by helium atom scattering. A dispersionless boson peak is seen at $6 \pm 0.5$ meV (1.5$ \pm$ 0.15 THz) and $-6 \pm 1.5$ meV ($-1.5 \pm 0.4$ THz), with reasonable evidence for a double excitation at $\pm 12 \pm 2.5$ meV ($2.9 \pm 0.6$ THz).
