Semiconductor based optically controlled THz optics

THz optics has experienced a tremendous increase in interest among the scientific community as better THz sources and detection schemes are discovered. With recent studies in THz modulation experiment using optically excited Si opens a new possibility in constructing THz optics using an optically controlled THz SLM. Thus, various patterns, such as zone lenses, could be optically constructed and tuned in real time for used in THz beam correction. For example, optically constructed Fresnel zone lenses on high-resistivity Si can be actively tuned for focal length and chromatic aberration, which are just some possible applications of this methodology. In this paper, we will present results for an optically controlled single pixeled THz semiconductor SLM for use as a modulator and discuss extensions to applications in zone lenses, diffraction gratings, and other optical components.

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