Romain, XavierXavierRomainWilshaw, Peter R.Peter R.WilshawStantchev, Rayko I.Rayko I.StantchevMiao, TinaTinaMiaoMuo, SenSenMuoNiewelt, TimTimNieweltMcNab, ShonaShonaMcNabPain, Sophie L.Sophie L.PainGrant, Nicholas E.Nicholas E.GrantBonilla, Ruy S.Ruy S.BonillaPickwell-MacPherson, EmmaEmmaPickwell-MacPhersonMurphy, John D.John D.Murphy2024-10-212024-10-212025Note-ID: 0000AFAAhttps://publica.fraunhofer.de/handle/publica/47780610.1109/TTHZ.2024.3477983Silicon-based terahertz (THz) photomodulators suffer from a modulation speed limited by the lifetime of the charge carriers photoexcited in the silicon. We report a silicon-based THz photomodulator scheme offering real-time reconfiguration of the switching behavior by manipulation of effective charge carrier lifetime. Atomic layer deposition was used to coat silicon samples with dielectric layers to passivate the surfaces with a conductive polymer (PEDOT:PSS) subsequently deposited to enable electrical gating over the whole surface. The resulting gated photomodulators are characterized using photoconductance decay and photoluminescence imaging. A gated photomodulator with HfO2 passivation is then implemented into a THz time domain spectroscopy setup to demonstrate the potential for live photomodulation optimization during a single-pixel imaging experiment. We use the device to achieve a real-time improvement of the signal-to-noise ratio of the images by a factor of 8.enjournal article