Current-induced birefringent absorption and non-reciprocal plasmons in graphene

Datum: 6 april 2016

Locatie: University of Antwerp - Campus Groenenborger - Room U.241 - Groenenborgerlaan 171 - 2000 Antwerp

Tijdstip: 16 - 17 uur

Organisatie / co-organisatie: Condensed Matter Theory

Korte beschrijving: Condensed Matter Theory seminar given by Ben van Duppen



Current-induced birefringent absorption and non-reciprocal plasmons in graphene

Upon passing a current through a graphene flake, the charge carriers are redistributed according to a drifted Fermi-Dirac distribution [1, 2]. The redistribution strongly affects the optical and plasmonic properties of the graphene sample. Due to the current, states laying higher than the chemical potential are populated while states laying underneath it are depleted. In this presentation, we demonstrate that this modifies the Pauli Blocking mechanism and that absorption acquires a birefringent character with respect to the angle between the in-plane light polarization and current flow [3]. Furthermore, we show that the Dirac plasmons [4] display a degree of non-reciprocity and that they are collimated in the downstream direction due the modification of the inter-band particle-hole continuum [3]. The birefringent absorption and plasmon non-reciprocity and collimation can be tuned by the applied current. All theoretically proposed effects are predicted to be prominent at room temperature in graphene flakes that are encapsulated by hexagonal boron nitride.

 

References

[1] V.F. Gantmakher and Y.B. Levinson, Carrier Scattering in Metals and Semiconductors (North-Holland, Amsterdam, 1987).

[2] R. Bistritzer and A.H. MacDonald, Phys. Rev. B 80, 085109 (2009).

[3] B. Van Duppen, A. Tomadin, A.N. Grigorenko, and M. Polini, 2D Mater. 3, 015011 (2016).

[4] A.N. Grigorenko, M. Polini, and K.S. Novoselov, Nature Photon. 6, 749 (2012).



Contact e-mail: lucian.covaci@uantwerpen.be

Url: http://cmt.uantwerpen.be