Theory of Detection of Terahertz Radiation in Hybrid Plasmonic Structures with Drifting Electron Gas

Abstract

The theory of non-linear interaction of electromagnetic radiation with hybrid plasmonic structure, which consists of the two-dimensional quantum heterostructure integrated with a plasmonic element in the form of a metal grating, is developed. In particular, the non-linear effect of a detection of high-frequency radiation by a drifting two-dimensional electron gas is examined. Based on the self-consistent solutions of the Maxwell and non-linear hydrodynamic equations in the frames of consistent perturbation theory of the second order, the expression of a photoresponse in the THz region is found. It is shown that the obtained expression contains an additional factor corresponding to the radiative decay rate. The latter was omitted in the previous theories. The presented theory is applied to the analysis of high-frequency properties of hybrid plasmonic structures on the basis of AlGaAs/GaAs quantum heterostructure. The influences of an optically thick substrate and the effect of the electron heating under high electron drifts on the spectral characteristics of the transmission/absorption coefficients and on the photoresponse spectra are analyzed. Some recommendations as for the design of efficient terahertz radiation detectors with the use of the hybrid plasmonic structures as a core element are given. K e y w o r d s: THz plasmonics, THz detection, hybrid plasmonic structures.

Modified rigorous coupled-wave analysis for grating-based plasmonic structures with delta-thin conductive channel. Far- and near-field study

“…2(c)). Moreover, we show that results of IE method [19,21,23], developed for the same plasmonic structure but delta-thin grating (see black dashed lines), and present RCWA for the grat- ing with h g = 0.05 µm almost coincide. An increase of the grating depth only leads to the additional dispersion of transmission and reflection coefficients in the higher frequency range.…”

“…Latter can be solved, for example, using Galerkin schemes with guaranteed convergence. The IE technique has been exploited for the different problems including investigations of 2D plasmon instabilities under the grating [8,19,20], detection of THz radiation [21][22][23] and interaction of THz radiation with conductive-strip gratings [24,25]. In spite of apparent advantages with respect to fast convergence, this method is typically formulated for modeling structures with simple geometries and grating is treated as delta-thin.…”

Selective terahertz emission due to electrically excited 2D plasmons in AlGaN/GaN heterostructure

“…To optimize the design of the structure purposed for investigation of THz emission related to grating-coupled 2D plasmons, we first performed the theoretical modeling of equilibrium transmission and absorption spectra for an AlGaN/GaN heterostructure with a surface metal grating. We considered the normal incidence of radiation and found a rigorous solution of Maxwell's equations applying the integral equation technique and the Galerkin scheme, 18,19 which give fast convergence and controlled accuracy of computations. Calculations were carried out for a temperature T ¼ 77 K.…”

THz properties of grating-gate plasmonic crystals

“…Although many aspects of grating-gate PCs have been examined theoretically by research groups led by Mikhailov [20], Popov [21,22] and Kochelap [23][24][25][26], a comprehensive exploration of the characteristics of these structures remains notably absent in the scientific literature. This knowledge gap can be attributed to two primary challenges.…”