Plasmons in a square of two-dimensional electrons

Complete electromagnetic consideration of plasmon mode excitation in graphene rectangles by incident terahertz wave

“…It is really instructive to compare the obtained results with the model of ideally reflecting boundaries for plasmons in graphene rectangle in the electrostatic approximation used in Ref. [16].…”

“…The ultimately most symmetrical shape of 2DES cavity in the form of circular disk (and ring) has been studied [9][10][11][12][13][14]. Much fewer papers are devoted to the plasmon excitation in a rectangular 2DES (including graphene) cavity [15][16][17]. A rectangular 2DES cavity has a reduced symmetry as compared to disk (or ring) geometry and therefore the theoretical consideration becomes more complex.…”

Complete electromagnetic consideration of plasmon mode excitation in graphene rectangles by incident terahertz wave

“…It is really instructive to compare the obtained results with the model of ideally reflecting boundaries for plasmons in graphene rectangle in the electrostatic approximation used in Ref. 18 .The ideal reflection boundaries model in the electrostatic approximation deals with the non-zero electric potential within the geometric area of graphene rectangle only and assumes it zero outside this area, while the complete electromagnetic approach that we employ considers the electric (and magnetic) fields in the whole space within and outside the geometric area of graphene rectangle self-consistently. Since the intraband transitions of charge carriers in graphene make a major contribution to the conductivity of graphene in THz frequencies, the contribution from the interband transitions can be neglected and the dispersion relation for plasmons in graphene (in the electrostatic approximation for lossless graphene) can be written as 36 , 37 where e is the elementary charge, q is the plasmon wave vector, and is the reduced Planck constant.…”

“…A rectangular 2DES cavity has a reduced symmetry as compared to disk (or ring) geometry and therefore the theoretical consideration becomes more complex. Theoretical approaches applied for studying the plasmon excitations in rectangular 2DES cavities employ either commercial numerical solvers 17 , 19 , 20 or use simplifying approximations 18 .…”

“…Lower-order plasmon modes in a square of 2DES in external magnetic field were studied both experimentally and theoretically in Ref. 18 . Plasmon resonances in graphene nanoribbons and nanoribbon arrays were investigated in Refs.…”