Emission of terahertz radiation from dual grating gate plasmon-resonant emitters fabricated with InGaP/InGaAs/GaAs material systems

Abstract

This paper reviews recent advances in our original 2D-plasmon-resonant terahertz emitters. The structure is based on a high-electron-mobility transistor and featured with doubly interdigitated grating gates. The dual grating gates can alternately modulate the 2D electron densities to periodically distribute the plasmonic cavities along the channel, acting as an antenna. The device can emit broadband terahertz radiation even at room temperature from self-oscillating 2D plasmons under the DC-biased conditions. When the device is subjected to laser illumination, photo-generated carriers stimulate the plasma oscillation, resulting in enhancement of the emission. The first sample was fabricated with standard GaAs-based heterostructure material systems, achieving room temperature terahertz emission. The second sample was fabricated in a double-decked HEMT structure in which the grating gate metal layer was replaced with the semiconducting upper-deck 2D electron layer, resulting in enhancement of emission by one order of magnitude.

Amplified-reflection plasmon instabilities in grating-gate plasmonic crystals

“…It is commonly accepted that the radiation appears as a result of plasmon excitation 1, [5][6][7] in 2DES and the subsequent coupling of plasmon to the free-space radiation upon interaction with single 7 or multiple 8 metal gates. The periodically gated 2DES typically demonstrate emission of higher power and narrower linewidth 4,9,10 compared to the plasmonic transistors with a single gate. Despite these experimental advances, there exists no accepted theory on the mechanism of plasmon self-excitation in grating-gated plasmonic nanostructures.…”

Transmission line theory of collective plasma excitations in periodic two-dimensional electron systems: Finite plasmonic crystals and Tamm states

“…These features make 2D plasmons an excellent candidate to be used for frequency tunable THz detection [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. The predicted instabilities of 2D plasma waves interacting with incident THz EM radiation also provide opportunities for designing THz sources [19][20][21].…”

3D-integration of a log spiral antenna onto a dual grating-gate plasmon-resonant terahertz emitter for high-directivity radiation

“…Two-dimensional (2D) plasmons in high-electron mobility transistors (HEMT's) have attracted attention due to their nature of instability promoting terahertz (THz) electromagnetic (EM) radiation, which is expected to realize integrated THz sources [1][2][3][4]. We have recently proposed a plasmonresonant THz emitter (PRE) [3,4], which is based on a InGaP/InGaAs/GaAs HEMT incorporating original doubly interdigitated grating gates (DGG's) acting as a broadband THz antenna ( Fig.…”

“…We have recently proposed a plasmonresonant THz emitter (PRE) [3,4], which is based on a InGaP/InGaAs/GaAs HEMT incorporating original doubly interdigitated grating gates (DGG's) acting as a broadband THz antenna ( Fig. 1(a)).…”