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Experimental results of low-power excitation of a 118 GHz TE(22,6) rotating mode are presented. A rectangular waveguide is converted to a TE(22,6) circular waveguide mode using quasi-optical techniques. A good conversion efficiency is measured and the expe ...
Distributed Brillouin gain measurements along single mode fibres have demonstrated their potentiality for local temperature sensing and monitoring strains experienced by optical fibres. The results of such measurements is directly related to the acoustic p ...
One of the most important parameters in the characterization of integrated optical waveguides is the precise determination of the effective cut-off wavelength of the fundamental and the first order mode, since it sets the exact region of single-mode operat ...
Birefringent single-mode fibers with random polarization mode coupling and polarization dependent losses are considered. The effect of these losses on polarization mode dispersion (PMD) is computed. The relevant number is found to be the differential loss ...
We present two interferometric techniques for the measurements of the polarization mode dispersion of standard (i.e. circular) single-mode fibers. The first method uses an interferometric loop and works in the frequency domain. The second uses a polarizati ...
The problem of mode competition in cylindrical cavity gyrotrons is considered. The normalized variable equations are used to calculate the oscillation regions of possible operating modes in the energy-velocity-pitch-angle plane. The analysis is self-consis ...
We discuss the growth of lattice matched GaInAs, GaInAsP and GaInAsP/GaInAs multiple quantum well structures for high speed laser applications. Optical cavities, including five 90 angstrom GaInAs quantum wells with GaInAsP barriers and waveguides showed a ...
The quality factor and oscillating mode of a gyrotron cavity are essential parameters to consider when trying to obtain a high power (>500 kW), high efficiency (∼50%) microwave source, which oscillates in a stable manner in the principal mode of the cavity ...
The operation of a 92 GHz quasi-optical gyrotron having a resonator formed by a spherical mirror and a diffraction grating placed in -1 order Littrow mount is presented. A power of 150 kW with a Gaussian output pattern was measured. The Gaussian content in ...