This Letter analyzes photoconductive (PC) terahertz (THz) emitters based on the semi-insulating (SI) forms of GaAs and InP. The dependencies of the emitters are studied under the extremes of the bias field and pump fluence to reveal the underlying physics of charge carrier photoexcitation, transport, and emission. The bias field dependence shows that SI-GaAs PC THz emitters are preferentially subject to space-charge-limited current, under the influence of trap states, while SI-InP PC THz emitters are preferentially subject to sustained current, due to a prolonged charge carrier lifetime and the ensuing joule heating.
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September 2018
In this work, the prospects of integrating terahertz (THz) time-domain spectroscopy (TDS) within polymer-based microfluidic platforms are investigated. The work considers platforms based upon the polar polymers polyethylene terephthalate (PET), polycarbonate (PC), polymethyl-methacrylate (PMMA), polydimethylsiloxane (PDMS), and the nonpolar polymers fluorinated ethylene propylene (FEP), polystyrene (PS), high-density polyethylene (HDPE), and ultra-high-molecular-weight polyethylene (UHMWPE). The THz absorption coefficients for these polymers are measured.
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