Related papers: Graphene Based Terahertz Phase Modulators
We introduce a systematic approach that enables two robust methods for performing terahertz time-domain spectroscopy in reflection geometry. Using the Kramers-Kronig relations in connection to accurate experimental measurements of the…
In this paper we propose and discuss coherent terahertz sources based on charge density wave (plasmon) amplification in two dimensional graphene. The coupling of the plasmons to interband electron-hole transitions in population inverted…
The nonlinear responses of different materials provide useful mechanisms for optical switching, low noise amplification, and harmonic frequency generation. However, the nonlinear processes usually have an extremely weak nature and require…
We present an experimental and numerical study of a terahertz metamaterial with a nonlinear response that is controllable via the relative structural positioning of two stacked split ring resonator arrays. The first array is fabricated on…
Recently, the strain engineering of two-dimensional materials such as graphene has attracted considerable attention for its great potential in functional nanodevices. Here, we theoretically and experimentally investigate the strain…
We propose the concept of a terahertz (THz) uncooled bolometer based on n-type and p-type graphene layers (GLs), constituting the absorbing regions, connected by an array of undoped graphene nanoribbons (GNRs). The GLs absorb the THz…
Graphene, a unique two-dimensional material of carbon in a honeycomb lattice, has brought remarkable breakthroughs across the domains of electronics, mechanics, and thermal transport, driven by the quasiparticle Dirac fermions obeying a…
We introduce an innovative graphene-based architecture to control electronic current flows. The tunable dot platform (TDP) consists of an array of gated dots, with independently adjustable potentials, embedded in graphene. Inspired by Mie…
We present a graphene-based metasurface that can be actively tuned between different regimes of operation, such as anomalous beam steering and focusing, cloaking and illusion optics, by applying electrostatic gating without modifying the…
The advancement in capabilities enabled by handheld devices and the prospective internet of things has led to an explosion of wireless data consumption in the last decade. The ever-increasing demand for high speed data transfer has…
Experimental realization of efficient graphene-based absorbers is a challenging task due to the low carrier mobility in processed graphene. In this paper, we circumvent this problem by placing uniform graphene sheets on metallic…
Developing low-power, high-sensitivity photodetectors for the terahertz (THz) band that operate at room temperature is an important challenge in optoelectronics. In this study, we introduce a photo-thermal-electric (PTE) effect detector…
Periodic metallic gratings on substrates can support a range of electromagnetic modes, such as leaky waveguide, guided-resonant, and Fabry-Perot (FP) cavity modes, which can strongly modulate optical transmission under resonant excitation.…
Topological Insulator-based devices can transport electrons/photons at the surfaces of materials without any back reflections, even in the presence of obstacles. Topological properties have recently been studied using non-reciprocal…
Uniaxial spintronic heterostructures constitute compact THz emitters under femtosecond optical excitation, with emission amplitude and polarization governed by the applied magnetic field is presented. We demonstrate here efficient…
Frequency-selective or even frequency-tunable Terahertz (THz) photodevices are critical components for many technological applications that require nanoscale manipulation, control and confinement of light. Within this context, gate-tunable…
Terahertz (THz) communications have been envisioned as a promising enabler to provide ultra-high data transmission for sixth generation (6G) wireless networks. To tackle the blockage vulnerability brought by severe path attenuation and poor…
We propose a terahertz radiation source based on the excitation of plasma resonances in graphene structures by means of mixing two NIR laser signals with a THz difference frequency. The process is the photo-thermo-electric effect which has…
Graphene is a two-dimensional crystal consisting of a monatomic layer of carbon atoms. Electrons and holes in graphene behave as quasi-relativistic particles with zero effective mass and large (as compared to semiconductors) Fermi velocity.…
This paper presents an efficient approach for exciting a dielectric resonator antenna (DRA) in the terahertz frequencies by means of a graphene plasmonic dipole. Design and analysis are performed in two steps. First, the propagation…