\Properties of plasmons in graphene traversed by electrons with arbitrary trajectories"

S. SEGUI; J. GERVASONI; K. AKBARI; Z. MISKOVIC; N. ARISTA

Gdansk

Conferencia; 13th. Int. Conf. on Surfaces, Coatings and Nanostructured materials (NANOSMAT); 2018

In recent papers we have developed a fully relativistic description of the energy losses suffered by an energeticelectron traversing perpendicularly a single layer of graphene (SLG) [1] as well as multilayered graphene stack(MLG) [2]. An extension of this work also considers the stopping of electrons travelling on parallel trajectoriesaloof a graphene layer [3].In the present work we develop the formalism for a generic oblique trajectory, and accordingly we consider atensorial in-plane conductivity with different components along the longitudinal and the transverse directionswith respect to the wave vector k. The formulation is made for a general conductivity and we apply differentmodels to describe both the low energy range (THz to mid-IR) and the UV range. In each case, we assess thecontributions coming from radiative as well as non-radiative (ohmic) losses, identifying the longitudinal andtransverse contributions. In this way, we analyze their dependence of with relevant parameters, like the electronvelocity and the incidence angle.[1] Z. L. Mi?ković, S. Segui, J. L. Gervasoni, and N. R. Arista, Phys. Rev. B 94, 125414 (2016)[2] K. Akbari, Z. L. Mi?ković, S. Segui, J. L. Gervasoni, and N. R. Arista, ACS Photonics 4, 1980 (2017).[3] Z. L. Mi?ković, K. Akbari, S. Segui, J. L. Gervasoni, and N. R. Arista, Nucl. Inst. and Meth. in Phys. Res.B 422, 18 (2018).[4] K. Akbari, Z. L. Mi?ković, S. Segui, J. L. Gervasoni, and N. R. Arista,Nanotechnology 29, 225201 (2018).