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arXiv · 1208.5209

Nexus between directionality of THz waves and structural parameters in groove-patterned InAs

Jong-Hyuk Yim·Kyunggu Min·Hoonil Jeong·Jin-Dong Song·Young-Dahl Jho
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Abstract

We have performed terahertz (THz)-time domain spectroscopy in various geometries, for characterizing the directivity of THz waves emitted from groove-patterned InAs structures. First, we have distinguished the THz emission mechanisms as a function of epilayer thickness. The carrier drift was predominant in thin sample group (10-70 nm) which the electronic diffusion motion was overriding the oppositely aligned drifting dipoles in thick sample group (370-900 nm) as revealed via amplitude and phase variations. By combined use of the electron-beam lithography and the inductively coupled plasma etching in 1 {\mu}m-thick InAs epilayers, we have further fabricated either asymmetric V-groove patterns or symmetric parabolic patterns. The THz amplitude was enhanced, particularly along line-of-sight transmissive direction when the groove patterns act as microscale reflective mirrors periodically separated by a scale of diffusion length.

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Jong-Hyuk Yim, Kyunggu Min, Hoonil Jeong, Jin-Dong Song, Young-Dahl Jho. 2012-08-26. Nexus between directionality of THz waves and structural parameters in groove-patterned InAs. https://doi.org/10.1063/1.4795541

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