Terahertz charge transport dynamics in 3D graphene networks with localization and band regimes

0572515 - FZÚ 2024 RIV GB eng J - Journal Article
Kumar, Prabhat - Šilhavík, Martin - Parida, Manas Ranjan - Němec, Hynek - Červenka, Jiří - Kužel, Petr
Terahertz charge transport dynamics in 3D graphene networks with localization and band regimes.
Nanoscale Advances. Roč. 5, č. 11 (2023), s. 2933-2940. ISSN 2516-0230. E-ISSN 2516-0230
R&D Projects: GA MŠMT EF16_026/0008382; GA MŠMT(CZ) EF16_019/0000760
EU Projects: European Commission(XE) 101028425 - 3D-AM-TERA
Grant - others:Ministerstvo školství, mládeže a tělovýchovy - GA MŠk(CZ) CZ.02.1.01/0.0/0.0/16_026/0008382; OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : terahertz * graphene * networks
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 4.7, year: 2022
Method of publishing: Open access

Terahertz steady-state and time-resolved conductivity and permittivity spectra were measured in 3D graphene networks assembled in free-standing covalently cross-linked graphene aerogels. Investigation of a transition between reduced-graphene oxide and graphene controlled by means of high-temperature annealing allowed us to elucidate the role of defects in the charge carrier transport in the materials. The THz spectra reveal increasing conductivity and decreasing permittivity with frequency. This contrasts with the Drude- or Lorentz-like conductivity typically observed in various 2D graphene samples, suggesting a significant contribution of a relaxational mechanism to the conductivity in 3D graphene percolated networks. The charge transport in the graphene aerogels exhibits an interplay between the carrier hopping among localized states and a Drude contribution of conduction-band carriers. Our findings provide important insight into the charge transport in complex graphene structures.
Permanent Link: https://hdl.handle.net/11104/0343184