Programme

P.23 -- Poster, ANSWCCMS-2023

Date: Tuesday, 7 November 2023

Time: 13:00 - 14:30

Topological phenomena polariton graphene

Olha M. Bahrova 1,2 and Sergei V. Koniakhin 1

1 Center for Theoretical Physics of Complex Systems, Institute for Basic Science, Daejeon, 34126, Republic of Korea 2 B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, 47 Nauky Ave., Kharkiv 61103, Ukraine

Topological photonics is among hot topics of modern physics nowadays. It opens a path towards the investigation of fundamentally new states of light and potential revolutionary applications. Further, exciton-polaritons (polaritons) take a special place among various photonic platforms due to their intrinsic non-linearity and possibility to control the wave function profile. On the other hand, the prominent properties that arise from the graphene type configuration, as Dirac-cone band structure, allow one to implement them in the field of photonics. There are extensive studies of the topological and transport properties of artificially created honeycomb lattices. At the same time, the spatial inversion symmetry breaking in electronic or mechanical systems can lead to the so-called ratchet effect. As a result, the nonlinear directed transport has its implementation in engineering and various fields of natural sciences. In graphene under asymmetric periodic strain the classical ratchet effect was considered [1], see also Ref. [2]. Further, the magnetic ratchet electron motion in a single graphene layer which is subject to the static magnetic and alternating electric fields, was observed in [3]. In addition, the ratchet effect due to asymmetric (skew) scattering [4] on trigonal defects has been theoretically investigated in [5]. The classical and quantum limits when the characteristic size of a defect is of order of the de Broglie wavelength, is taken into account. We consider a polariton analog of a single-layer graphene. In order to investigate time evolution of a wave packet, we perform numerical simulations using the corresponding Gross-Pitaevskii equation. Besides, for the considered system the spatial symmetry is broken via embedding of triangle-shaped defects. We reveal the presence of ratchet motion as a consequence of the scattering on defects. Moreover, the results of our numerical calculations are in the agreement with analytical predictions for skew scattering in graphene. References [1] A.V. Nalitov, L.E. Golub, E.L Ivchenko, Phys. Rev. B 86, 115301 (2012). [2] E. M ̈onch et al., Phys. Rev. B 105, 045104 (2022). [3] C. Drexcler et al., Nature Nanotech. 8, 104 (2013). [4] V.I. Belinicher, B.I. Sturman, Sov. Phys. Usp. 23, 199 (1980). [5] S.V. Koniakhin, Eur. Phys. J. B 87, 216 (2014).

Presenter: Olha M. Bahrova