相关论文: Advantages of optical modulation in terahertz imag…
Electrically tuneable high mobility charges on graphene yield an efficient electro-optical platform to control and manipulate terahertz (THz) waves. Real-world applications require a multiplex THz device with efficient modulation over a…
We demonstrate efficient terahertz (THz) modulation by coupling graphene strongly with a broadband THz metasurface device. This THz metasurface, made of periodic gold slit arrays, shows near unity broadband transmission, which arises from…
Electrical control of amplitude and phase of terahertz radiation (THz) is the key technological challenge for high resolution and noninvasive THz imaging. The lack of an active materials and devices hinders the realization of these imaging…
Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene's unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz…
Among its many outstanding properties, graphene supports terahertz surface plasma waves -- sub-wavelength charge density oscillations connected with electromagnetic fields that are tightly localized near the surface[1,2]. When these waves…
Effective control of terahertz radiation requires the development of efficient and fast modulators with a large modulation depth. This challenge is often tackled by using metamaterials, artificial sub-wavelength optical structures…
We report a terahertz optical modulator consisting of randomly stacked trilayer graphene (TLG) deposited on an oxidized silicon substrate by means of THz- Time Domain Spectroscopy (THz-TDS). Here, the gate tuning of the Fermi level of the…
We analyze the modulation characteristics of the uncooled terahertz (THz) and infrared (IR) detectors using the variation of the density and effective temperature of the two-dimensional electron-hole plasma in uniform graphene layers (GLs)…
For optical communication, information is converted between optical and electrical signal domains at a high rate. The devices to achieve such a conversion are various types of electro-optical modulators and photodetectors. These two types…
We report a highly efficient tunable THz reflector in graphene. By applying a small gate voltage (up to 3 V), the reflectance of graphene is modulated from a minimum of 0.79% to a maximum of 33.4% using graphene/ionic liquid structures at…
Graphene based THz modulators are promising due to the conical band structure and high carrier mobility of graphene. Here, we tune the Fermi level of graphene via electrical gating with the help of ionic liquid to control the THz…
The unique optoelectronic properties of graphene [1] make it an ideal platform for a variety of photonic applications [2], including fast photodetectors [3], transparent electrodes [4], optical modulators [5], and ultra-fast lasers [6].…
A simple optical method is presented for identifying and measuring the effective optical properties of nanometer-thick, graphene-based materials, based on the use of substrates consisting of a thin dielectric layer on silicon. High contrast…
Exploration of optical non-linear response of graphene predominantly relies on ultra-short time domain measurements. Here we propose an alternate technique that uses frequency modulated continuous wavefront optical fields, thereby probing…
The efficient modulation and control of ultrafast signals on-chip is of central importance in terahertz (THz) communications and a promising route toward sub-diffraction limit THz spectroscopy. Two-dimensional (2D) materials may provide a…
We propose and analyze the detector of modulated terahertz (THz) radiation based on the graphene field-effect transistor with mechanically floating gate made of graphene as well. The THz component of incoming radiation induces resonant…
We propose and discuss terahertz electro-absorption modulators based on graphene plasmonic structures. The active device consists of a self-gated pair of graphene layers, which are patterned to structures supporting THz plasmonic…
Graphene plasmons hold immense potential for terahertz (THz) detector application due to their fascinating interactions between radiation and matter. However, it has remained challenging to excite and manipulate graphene plasmons within…
We study the interaction between polarized terahertz (THz) radiation and micro-structured large-area graphene in transmission geometry. In order to efficiently couple the radiation into the two-dimensional material, a lateral periodic…
We present the experimental and theoretical study of an ultrafast graphene based thin film absorption modulator for operation in the THz regime. The flat modulator is composed of a graphene sheet placed on a dielectric layer backed by a…