Spectrum of Cherenkov Radiation in Dispersive Metamaterials With Negative Refraction Index

Abstract

Abstract-We numerically studied the spectrum of Cherenkov optical radiation by a nonrelativistic anisotropic electron bunch crossing 3D dispersive metamaterial. A practically important case when such a medium is described by Drude model is investigated in details. In our theory only parameters of a metamaterial are fixed. The frequency spectrum of internal excitations is left to be defined as a result of the numerical simulation. It is found that a periodic field structure coupled to plasmonic excitations is arisen when the dispersive refractive index of a metamaterial becomes negative. In this case the reversed Cherenkov radiation is observed.

Change of Structure of the Cherenkov Emission at Modulated Source in Dispersive Metamaterials

“…1(a) depicts the case ω 0 = 0; in this situation only the spectrum of the periodic plasmonic excitations with the frequency ω C and negative phase velocity is observed (see details in Ref. [11]). At the increase of ω 0 up to 6 (see Figs.…”

“…For such angle we have [11] cos(θ) = sin(θ 1 ) = c/nv 0 , so for conventional material (with Re(n) > 0) θ 1 is positive θ 1 = θ 1+ > 0, while for negative refraction index metamaterial NIM (with Re(n) < 0) θ 1 is negative θ 1 = θ 1− < 0. From Fig.…”

“…In our simulations was used the numerical grid L 3 , L = 100, 120, 150, for more details see Ref. [11].…”

“…In this paper, the well-known numerical algorithms in the time domain [31] were used, for details see Ref. [11].…”

An Ultra-Low Loss Split Ring Resonator by Suppressing the Electric Dipole Moment Approach

“…Negative index metamaterials (NIMs) have attracted great attention due to their fascinating electromagnetic (EM) properties such as perfect lens, near-field imagings, cloakings, reversal of the Doppler effects, and so on [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. A well-established route of constructing NIM structures is based on the Veselago's theory of left-handed materials (LHM), simultaneous negative permittivity and permeability [16].…”