Time resolution and dynamic range of field effect transistor based terahertz detectors

Abstract

We studied time resolution and response power dependence of three terahertz detectors based on significantly different types of field effect transistors. We analyzed the photoresponse of custom-made Si junctionless FETs, Si MOSFETs and GaAs-based high electron mobility transistors detectors. Applying monochromatic radiation of high power, pulsed, line-tunable molecular THz laser, which operated at frequencies in the range from 0.6-3.3 THz, we demonstrated that all these detectors have at least nanosecond response time. We showed that detectors yield a linear response in a wide range of radiation power. At high powers the response saturates varying with radiation power P as $U=R_{0}P/(1+P/P_s)$, where $R_0$ is the low power responsivity, $P_s$ is the saturation power. We demonstrated that the linear part response decreases with radiation frequency increase as $R_0\propto f^{-3}$, whereas the power at which signal saturates increases as $P_s\propto f^3$. We discussed the observed dependences in the framework of the Dyakonov-Shur mechanism and detector-antenna impedance matching. Our study showed that FET transistors can be used as ultrafast room temperature detectors of THz radiation and that their dynamic range extends over many orders of magnitude of power of incoming THz radiation. Therefore, when embedded with current driven read out electronics they are very well adopted for operation with high power pulsed sources.

References in corpus (9)

• Graphene field effect transistors as room-temperature Terahertz detectors
• Field Effect Transistors for Terahertz Detection: Physics and First Imaging Applications
• Cyclotron Resonance Assisted Photocurrents in Surface States of a 3D Topological Insulator Based on a Strained High Mobility HgTe Film
• Quantum ratchet effects induced by terahertz radiation in GaN-based two-dimensional structures
• Giant spin-polarized current in a Dirac fermion system at cyclotron resonance
• Classical ratchet effects in heterostructures with a lateral periodic potential
• Helicity sensitive terahertz radiation detection by field effect transistors
• High intensity study of THz detectors based on field effect transistors
• Performance Limits for Field Effect Transistors as Terahertz Detectors