Size-dependent hot-phonon dynamics in graphene flakes

作者：Cunning Benjamin V^*; Ishioka Kunie; Brown Christopher L; Kielpinski Dave

来源：Applied Physics Letters, 2014, 104(18): 181907.

DOI：10.1063/1.4875580

We examine the ultrafast carrier phonon dynamics in graphene flakes with different lateral sizes. By using a size-selective centrifugation technique, we create graphene films with graphene flake sizes in the region of 120-450 nm. The transient transmission exhibits two-step relaxation, which are attributed to carrier thermalization followed by hot phonon cooling. We find that the cooling of the hot phonons proceeds faster, by a factor of three, for the smallest graphene flakes.

• 出版日期2014-5-5