Terahertz detection using on chip patch and dipole antenna-coupled GaAs High Electron Mobility Transistors

This paper presents high responsivity plasmonic terahertz (THz) power detectors operating at 0.3 THz. The detectors are implemented using 130 nm depletion mode InGaAs/GaAs pseudomorphic High Electron Mobility Transistors (pHEMT) with on chip patch and dipole antennas connected to the gate terminal. The measured absolute responsivity at room temperature is 7V/W, while the normalized responsivity with respect to the THz beam and physical antenna area is 8kV/W, with a noise equivalent power (NEP) of 9.1 pW/√(Hz). The paper also addresses the bias dependency of the signal to noise ratio (SNR), THz detector input impedance and the matching requirement for the connection between the antenna and input to the gate of the THz detector.