Generation of ultrashort electrical pulses in semiconductor waveguides

Abstract

Abstract-In this letter, we report a novel device capable of generating ultrashort electrical pulses on a coplanar waveguide (CPW) by means of optical rectification. The device consists of a completely passive GaAs-based optical waveguide, which is velocity matched to a CPW line. Optical pulses are injected into the device and electrical pulses are collected at the output. Experimental results obtained in the laboratory show the potential of this device for high speed optical-to-electrical conversion.

<title>Breather-like pulses in a medium with the permanent dipole moment</title>

“…The conclusions made above are most obvious for the pulses with slowly varying envelope. Indeed, if condition ΩT ≫ 1 holds, then formulas (12) and (13) become simpler:…”

“…For example, an anisotropic medium, in which the modulus of the ratio between PDM and corresponding off-diagonal matrix element of the dipole moment operator lies for different quantum transitions within the limits from 0.15 up to 7.1, is resulted in work 1 . Besides, one of the persistent trends in developing the laser physics is to obtain the most shorter pulses 11,12 .…”

Design of a continuous-wave tunable terahertz source using waveguide-phase-matched GaAs

“…However, GaAs has been used in several electro-optic devices based on other related types of nonlinear interactions in which phase-matching is provided using wave-guiding techniques [6]- [9]. In the case of GaAs based optical modulators or up-converters, integration of a slab waveguide and slow-wave coplanar electrodes is used to phase match the optical and RF signals [7].…”

“…Dependency of the supported terahertz frequency on dimensions of the ridge waveguide results in narrowband terahertz operation. A co-planar waveguide on top of a ridge slab optical waveguide has also been used as an optical rectifier to generate ultra-short pulses in GaAs [9].…”