| Popis: |
We review the phonon thermal properties of graphene and twisted bilayer graphene, and discuss dependence of the thermal conductivity on the sample size and shape, edge quality, and defects in crystal lattice. We discuss the rotational-dependent phonon modes in twisted bilayer graphene resulting in an intriguing dependence of the specific heat and thermal conductivity on the twist angle. The dispersion of the out-of-plane acoustic phonons – referred to as ZA phonons – deviates strongly from a parabolic law starting from the frequencies as low as ∼ 100 cm−1. This leads to the frequency-dependent ZA phonon density of states and the breakdown of the linear dependence of the specific heat on temperature. The chapter also overviews the experimental and modeling results pertinent to thermal properties of graphene, which indicate that graphene and its derivatives are promising material for thermal management and heat removal applications. |
