Generation of subpicosecond electrical pulses by nonuniform illumination of GaAs transmission-line gaps

Author

Alexandrou, Sotiris ; Wang, Chia-Chi ; Sobolewski, Roman ; Hsiang, Thomas Y.

Author_Institution

Lab. for Laser Energetics, Rochester Univ., NY, USA

Volume

30

Issue

5

fYear

1994

fDate

5/1/1994 12:00:00 AM

Firstpage

1332

Lastpage

1338

Abstract

We present a detailed study of subpicosecond pulse generation by nonuniform illumination of transmission-line gaps on semiinsulating GaAs. The dependence of such pulses on bias voltage, light intensity, and wavelength was examined in detail with the aid of a subpicosecond electrooptic sampling system. A complete spatial mapping of the excitation area indicates that the pulse generation is due to the depletion of the electrical field in the illuminated section of the gap. A comparison of uniform and nonuniform gap excitation schemes pinpointed the physical differences between the two processes of electrical-transient generation. Picosecond pulses were also generated by nonuniform illumination of a photoconductive gap placed in series with a coplanar waveguide for the first time and were found to contain balanced, odd modes only

Keywords

III-V semiconductors; electro-optical devices; gallium arsenide; photoconducting devices; GaAs; GaAs transmission-line gaps; balanced odd modes; bias voltage; coplanar waveguide; electrical field; electrical-transient generation; excitation area; light intensity; nonuniform gap excitation; nonuniform illumination; photoconductive gap; pulse generation; semiinsulating GaAs; spatial mapping; subpicosecond electrical pulses; subpicosecond electrooptic sampling system; uniform gap excitation; Electrodes; Gallium arsenide; Lighting; Optical propagation; Optical pulse generation; Optical pulses; Photoconductivity; Pulse generation; Switches; Transmission lines;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/3.303699

Filename

303699