We present an approach for efficient conversion of a single-high-order-mode distribution from a laser to a nearly Gaussian distribution and vice versa. It is based on dividing the high-order mode distribution into equal parts that are then combined together coherently. We implement our approach with several optical arrangements that include a combination of discrete elements and some with singl...

A scheme for the excitation of slow surface plasmon pulses using photonic interband transition in a metal-insulator-metal (MIM) waveguide is proposed. An investigation the mode transition behavior inside the binary grating confirmed that the proposed concept can be understood in terms of the coupling of symmetric and anti-symmetric plasmonic modes. We observed that, although a binary grating th...

The first demonstration of electron-Bernstein-wave heating by double-mode conversion from the O to the X mode in an overdense H-mode tokamak plasma has been achieved in the Tokamak à Configuration Variable device. This technique overcomes the upper density limit experienced by conventional microwave heating. The sensitive dependence of the O-X mode conversion on the microwave launching directio...

We study resonant mode conversion in the  -symmetric multimode waveguides, where symmetry breaking manifests itself in sequential destabilization (appearance of the complex eigenvalues) of the pairs of adjacent guided modes. We show that the efficient mode conversion is possible even in the presence of the resonant longitudinal modulation of the complex refractive index. The distinguishing fe...

Blackbody levels of emission in the electron cyclotron range of frequencies have been observed from an overdense (vpe;3vce) Madison Symmetric Torus @Dexter et al., Fusion Technol. 19, 131 ~1991!# reversed field pinch plasma, a result of electrostatic electron Bernstein waves emitted from the core and mode converted into electromagnetic waves at the extreme plasma edge. Comparison of the measure...

The ITER ECH Transmission Lines (TLs) are 63.5 mm diameter corrugated waveguides that will each carry 1 MW of power at 170 GHz with a transmission efficiency that should exceed 83%. The losses on the ITER TL have been calculated for four possible cases corresponding to having HE11 mode purity at the input of the TL of 100%, 97%, 90% and 80%. The losses due to coupling, Ohmic and mode conversion...

The trans-admittance-mode (TAM) might act as a transforming bridge for voltage-mode to current-mode conversion. In this study a new low voltage operated electronically tunable TAM biquad filter structure realizing all the seven standard filtering functions namely; low-pass (LP), band-pass (BP), high-pass (HP), regular-notch (RN), low-pass-notch (LPN), high-pass-notch (HPN) and all-pass (AP) fro...