石墨烯声子谱研究

Phonon Spectrum of Graphene

石墨烯的成功制备是纳米材料研究的重大进展。人们发现其具有很高的热导率,从而为解决计算机芯片散热问题提供了一条可能的方案。文章主要应用动力学矩阵的方法,计算了Tersoff势下石墨烯的声子谱,并探讨了该势在研究石墨烯热学性质方面的合理性。通过与实验数据的比较,我们发现,使用Tersoff势得到的声子谱在高对称点处的能量误差最大可以达到70%。因此,Tersoff势不适合于对石墨烯的热学性质进行定量的研究。

Discovery of graphene is a breakthrough in the field of nanomaterials.People find that the thermal conductivity of graphene is extremely high so that it provides a possible way to solve the heat sink of computer chip.In this paper,we use the dynamic matrix method to calculate the phonon spectrum of Tersoff potential of graphene and discuss the feasibility of Tersoff potential in the aspect of studying the thermal properties of graphene.By means of comparing our phonon spectrum with experiments,we find that the maximum energy error of our spectrum at the points of high symmetry is 70%.Therefore,Tersoff potential is not a good choice in studying the thermal properties of graphene quantitatively.