Tuning quantum non-local effects in graphene plasmonics

Date: 21 December 2016

Venue: UAntwerp, Campus Groenenborger, building U, room 241 - Groeneborgerlaan 171 - 2020 Antwerpen (route: UAntwerpen, Campus Groenenborger)

Time: 4:00 PM - 5:00 PM

Organization / co-organization: Condensed Matter Theory

Short description: Condensed Matter Theory seminar presented by Dr Ben Van Duppen

Tuning quantum non-local effects in graphene plasmonics

The response of an electron system to short range electromagnetic fields is strongly dependent on quantum electronic properties, even under ambient conditions, but difficult to access experimentally. We use high-quality graphene plasmons, together with an engineered dielectric–metallic environment, to access this regime of short-ranged response, where non-local effects due to quantum properties become significant. We clearly identify three types of quantum effects as keys to understanding the experimental response of graphene to short-ranged terahertz electric fields. The first type is of single-particle nature and is related to shape deformations of the Fermi surface during a plasmon oscillation. The second and third types are a quantum many-body effect controlled by the inertia and compressibility of the interacting electron liquid in graphene. We demonstrate how, in principle, experiments can determine the full spatiotemporal response of an electron system.

Contact email: lucian.covaci@uantwerpen.be

Link: http://cmt.uantwerpen.be