Related papers: Ultrafast graphene-based broadband THz detector
Terahertz (THz) and sub-THz frequency emitter and detector technologies are receiving increasing attention, underpinned by emerging applications in ultra-fast THz physics, frequency-combs technology and pulsed laser development in this…
Graphene has been one of the most investigated materials in the last decade. Its unique optoelectronic properties have indeed raised it to an ideal and revolutionary candidate for the development of entirely novel technologies across the…
Graphene is a promising material for nonlinear THz applications owing to its high third-order susceptibility and tunable optical properties. Its strong nonlinear response, driven by free-carrier thermodynamics, facilitates efficient…
Flexible energy harvesting devices fabricated in scalable thin-film processes are important components in the field of wearable electronics and the Internet of Things. We present a flexible rectenna based on a one-dimensional junction…
Ultrafast dynamics of graphite is investigated by time-resolved photoemission spectroscopy. We observe spectral features of direct photoexcitations, non-thermal electron distributions, and recovery dynamics occurring with two time scales…
We present a combined experimental and theoretical study of photovoltage generation in a bilayer graphene (BLG) transistor structure exposed to subterahertz radiation. The device features a global bottom and split top gate, enabling…
Plasmons, collective oscillations of electron systems, can efficiently couple light and electric current, and thus can be used to create sub-wavelength photodetectors, radiation mixers, and on-chip spectrometers. Despite considerable…
Hot electron effects in graphene are significant because of graphene's small electronic heat capacity and weak electron-phonon coupling, yet the dynamics and cooling mechanisms of hot electrons in graphene are not completely understood. We…
In order to increase the response speed of the InSe-based photodetector with high photoresponsivity, graphene is used as the transparent electrodes to modify the difference of the work function between the electrodes and the InSe. As…
A fast silicon-graphene hybrid plasmonic waveguide photodetectors beyond 1.55 {\mu}m is proposed and realized by introducing an ultra-thin wide silicon-on-insulator ridge core region with a narrow metal cap. With this novel design, the…
We analyze the performance of graphene microstructures as thermal photon detectors and deduce the range of parameters that define a linear response. The saturation effects of a graphene thermal detector that operates beyond the linear range…
Graphene is at the center of a significant research effort. Near-ballistic transport at room temperature and high mobility make it a potential material for nanoelectronics. Its electronic and mechanical properties are also ideal for micro…
The efficient amplification and lasing of electromagnetic radiation at terahertz (THz) frequencies is a non-trivial task achieved mainly by quantum cascade laser configurations with limited tunability and narrowband functionality. There is…
Graphene photodetectors offer ultrafast response and broadband operation, but their responsivity is typically limited by rapid hot-carrier cooling, leading to a trade-off between sensitivity and speed. Here, we demonstrate that modifying…
Graphene is widely recognized for its ultrafast and broadband photocurrent response, but whether the broadband ultrafast characteristics are preserved at mid-infrared wavelengths with photon energies below the optical phonon energy remains…
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…
By exploiting singular spatial modulations of the graphene conductivity, we design a broadband, tunable THz absorber whose efficiency approaches the theoretical upper bound for a wide absorption band with a fractional bandwidth of 185\%.…
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…
Electrically injected terahertz (THz) radiation sources are extremely appealing given their versatility and miniaturization potential, opening the venue for integrated-circuit THz technology. In this work, we show that coherent THz…
Observations of solar flares at sub-THz frequencies (mm and sub-mm wavelengths) over the last two decades often show a spectral component rising with frequency. Unlike a typical gyrosynchrotron spectrum decreasing with frequency, or a weak…