Graphene active plasmonics for terahertz device applications

Abstract

This paper reviews recent advances in the double-graphene-layer (DGL) active plasmonic heterostructures for the terahertz (THz) device applications. The DGL consists of a core shell in which a thin tunnel barrier layer is sandwiched by the two GLs being independently connected with the side contacts and outer gate stack layers at both sides. The DGL core shell works as a nano-capacitor, exhibiting inter-GL resonant tunneling (RT) when the band offset between the two GLs is aligned. The RT produces a strong nonlinearity with a negative differential conductance in the DGL current-voltage characteristics. The excitation of the graphene plasmons by the THz radiation resonantly modulates the tunneling currentvoltage characteristics. When the band offset is aligned to the THz photon energy, the DGL structure can mediate photonassisted RT, resulting in resonant emission or detection of the THz radiation. The cooperative double-resonant excitation with structure-sensitive graphene plasmons gives rise to various functionalities such as rectification (detection), photomixing, higher harmonic generation, and self-oscillation, in the THz device implementations.

Graphene based functional devices: A short review

“…Due to its large conductivity swing, graphene has attracted lots of attention as a material for terahertz modulators [116][117][118][119]. Since 2010s, there have been many reports for a large modulation depth and broadband operation in the terahertz regime by actively controlling the carrier concentration of a graphene layer and via the integration of graphene with metamaterials [13,[116][117][118][119][120][121][122][123][124][125][126][127][128][129][130][131]. In 2012, Sensale-Rodriguez et al [132] developed a broadband graphene terahertz electro-absorption modulator.…”

Manifestation of Kinetic Inductance in Terahertz Plasmon Resonances in Thin-Film Cd3As2

“…The presence of strong coupling of terahertz radiation, in conjunction with facile tunable response and a long momentum scattering time (τ) in these materials, has been envisioned to play a critical role in the burgeoning field of terahertz electronics and optoelectronics. In this regard, research efforts to-date have been mainly driven by studies of plasmons in two-dimensional (2D) graphene [20,21]. Interestingly, long anticipated, threedimensional (3D) analogues of graphene, i.e.…”

Effect of electron momentum relaxation time on the terahertz properties of graphene structures

“…1 employing different values for the electron momentum relaxation time in accordance with the discussion in e.g. [5][6]. In our simulations, the graphene layer, was modeled employing a finite thickness (one nanometer) following the procedure employed in [17][18][19][20].…”

“…In this context, graphene based plasmonics have obtained much attention for terahertz modulation, filtering, and even detection and generation [2][3][4][5][6][7][8][9]. In this work we study the effect of electron momentum relaxation time on the response of graphene plasmonic structures.…”