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Terahertz (THz) plasmonic devises based on periodical corrugated structures are promising for sensing applications in biology and medicine but have not been developed so far because spoof surface plasmons (SSPs) on such structures were studied insufficiently in the THz spectral range. In the paper, the propagation of THz SSPs along one-dimensional subwavelength rectangular plane gratings with a dielectric...
Within the quasi-optical approach, we study evanescent waves propagation along a periodically corrugated surface and their excitation by a relativistic electron beam. The main features of amplifier and oscillators schemes are described including the increments, starting currents, electron efficiency and forming of self-consistent spatial structure of the radiation field. The feasibility of realization...
A new scheme of terahertz band FEL with hybrid Bragg resonator is proposed consisting of an advanced input Bragg mirror and a traditional output Bragg mirror. Advanced Bragg mirror exploiting the coupling between the two counter propagating modes and the cutoff one provides mode selection over the transverse index.
In this paper the authors consider the planar model of the FEL with a hybrid resonator consisting of two Bragg structures with different operating features: an upstream (cathode-side) advanced and a downstream (collector-side) traditional Bragg reflectors. Mode control in the transverse direction is achieved in the upstream advanced Bragg reflector due to additional transverse electromagnetic energy...
Possibility of realization of terahertz planar FEL is demonstrated based on advanced Bragg reflectors exploiting the coupling between propagating and quasi cut-off modes. Such structure allows providing spatial coherence radiation on two coordinates for large oversize of interaction space.
A model of a laser exploiting two-dimensional (2D) distributed feedback is developed. A new feedback mechanism can be realized using a dielectric structure with the width having double-periodical sinusoidal or chessboard modulation. It is shown that 2D Bragg resonator possesses high selectivity over both the longitudinal and the transverse indices. Within semi-classical approach nonlinear dynamics...
A planar narrow band Bragg reflector based on coupling of propagating and quasi-cutoff modes is considered. Coupled waves analysis together with direct numerical simulations demonstrate the operability of novel scheme up to THz frequency band.
A novel Bragg FEM scheme [1] is discussed in which an electron beam synchronously interacts with a propagating wave, and the latter is coupled to a quasi cut-off mode. This coupling is realized by either helical or asimuthally symmetric corrugation of the waveguide walls. The quasi cut-off mode provides feedback in the system leading to self-excitation of the whole system while the energy extraction...
We study wave propagation in a open oversized planar waveguide with periodical Bragg structure, translation vector of which is perpendicular to the direction of wave propagation. Such waveguide can be realized either in a medium with periodic modulation of dielectric constant or in planar waveguide with corresponding corrugation. It is shown that step of corrugation phase provides the existence of...
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