A plasmonic terahertz detector with a monolithic hot electron bolometer

A plasmonic terahertz detector that integrates a voltage-controlled planar barrier into a grating gated GaAs/AlGaAs high electron mobility transistor has been fabricated and experimentally characterized. The plasmonic response at fixed grating gate voltage has a full width at half-maximum of 40 GHz at ∼405 GHz. Substantially increased responsivity is achieved by introducing an independently biased narrow gate that produces a lateral potential barrier electrically in series with the resonant grating gated region. DC electrical characterization in conjunction with bias-dependent terahertz responsivity and time constant measurements indicate that a hot electron bolometric effect is the dominant response mechanism at 20 K.