Plasmonic noise of field-effect transistors operating at terahertz frequencies

Abstract

We analyze electronic noise in field-effect transistors associated with plasma waves in the terahertz frequency domain by using a numerical approach based on the coupled hydrodynamic and Poisson equations. The current and voltage noise spectra, calculated by means of the transfer impedance method, exhibit a series of peaks associated with two- and three-dimensional plasma resonances. The two-dimensional plasma peaks have been found to depend on the channel length including gated and ungated regions. Under asymmetric boundary conditions, electrical instabilities characterized by terahertz oscillations of the drain voltage and gate current can be reached at sufficiently high values of the total drain current. A resonant enhancement of the plasma peaks in the noise spectra has been found to be a precursor of the instability onset. Through a spatial analysis of the local contributions we have shown that the main contribution to the total noise at frequencies near the plasma resonance comes from the ungated n-region placed between the source and the gate contacts.

Introduction: Unsolved Problems on Noise

“…As expected, noise in graphene materials and devices had a relevant repercussion in the conference [17][18][19]. Similarly, investigations on the plasmonic noise in terahertz electronic devices were also discussed [19,20]. In [21] the occurrence of noise reduction eect in semiconductors embedded in sub-THz electric fields is studied.…”

Optimizing Terahertz Signal Detection in High Electron Mobility Transistors: Insights from Plasma Resonance Studies

“…To determine the remaining primary physical quantities, such as current density J and electric field E, a coupling was established between the hydrodynamic equations and the pseudo-2D Poisson equation [24,25]. This integrated approach bestowed upon us the capacity to comprehensively analyze and understand the intricate interplay between various parameters and phenomena within the HEMT device, thereby providing valuable insights into the plasmonic THz detection process.…”

“…This integrated approach bestowed upon us the capacity to comprehensively analyze and understand the intricate interplay between various parameters and phenomena within the HEMT device, thereby providing valuable insights into the plasmonic THz detection process. The fundamental physical quantities, current density J, and electric field E, were founded through the coupling of the hydrodynamic equations with the pseudo-2D Poisson equation, as represented by Equation (1.2) [25]:…”