Roger W. McGowan

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We report experimental investigations in which quasi-optical methods were used to efficiently couple freely propagating, optoelectronically generated, subpicosecond pulses of terahertz (THz) radiation into submillimeter circular metal tubes (waveguides) and, consequently, to measure the transmitted pulses from these waveguides. We observe very dispersive(More)
The surface-wave scattering processes responsible, in part, for the optical glory have never been compared with theoretical predictions. Here, THz impulse ranging is used to measure the time domain impulse response of spherical targets with sufficiently high temporal resolution to permit the surfacewave contribution to the total impulse response to be(More)
Employing an ultrafast optoelectronic terahertz impulse radar range with subpicosecond resolution, we have characterized the electric-field time-domain response from an impulsively excited dielectric cylinder. The bandwidth of the measurement extends from 200 GHz to 1.4 THz and late time response is observed at times exceeding that to traverse 40 target(More)
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