2016/12/24 by Prineha Narang, Litao Zhao, Narang, Prineha +5
Materials Science · Physics and Astronomy · #2D Materials and Applications #Computational Physics (physics.comp-ph) #FOS: Physical sciences #Graphene research and applications #Materials Science (cond-mat.mtrl-sci) #Optics (physics.optics) #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.1612.08196
openalex publication_date 2016/12/24 · openalex created_date 2022/08/16 · openalex updated_date 2026/07/28
Graphene exhibits promise as a plasmonic material with high mode confinement\nthat could enable efficient hot carrier extraction. We investigate the\nlifetimes and mean free paths of energetic carriers in free-standing graphene,\ngraphite and a heterostructure consisting of alternating graphene and hexagonal\nboron nitride layers using ab initio calculations of electron-electron and\nelectron-phonon scattering in these materials. We find that the extremely high\nlifetimes (3 ps) of low-energy carriers near the Dirac point in graphene, which\nare a hundred times larger than that in noble metals, are reduced by an order\nof magnitude due to inter-layer coupling in graphite, but enhanced in the\nheterostructure due to phonon mode clamping. However, these lifetimes drop\nprecipitously with increasing carrier energy, and are smaller than those in\nnoble metals at energies exceeding 0.5 eV. By analysing the contribution of\ndifferent scattering mechanisms and inter-layer interactions, we identify\ndesirable spacer layer characteristics - high dielectric constant and heavy\natoms - that could pave the way for plasmonic heterostructures with improved\nhot carrier transport.\n