Related papers: Ultrafast graphene-based broadband THz detector
Since graphene has no band gap, photoluminescence is not expected from relaxed charge carriers. We have, however, observed significant light emission from graphene under excitation by ultrashort (30-fs) laser pulses. Light emission was…
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…
Graphene-based photodetectors, taking advantage of high carrier mobility and broadband absorption in graphene, have recently experienced rapid development. However, their performances with respect to the responsivity and bandwidth are still…
Epitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale. The THz near-field images show variation of…
The unique optoelectronic properties of single layer graphene (SLG) are ideal for the development of photonic devices across a broad range of frequencies, from X-rays to microwaves. In the terahertz (THz) range (0.1-10 THz frequency) this…
Using a spatially structured, optical pump pulse with a THz probe pulse, we are able to determine spatial variations of the ultrafast THz photoconductivity with sub-wavelength resolution (75 $\mu m \approx \lambda/5$ at 0.8 THz) in a planar…
Optical excitation and subsequent decay of graphene plasmons can produce a significant increase in charge-carrier temperature. An efficient method to convert this temperature elevation into a measurable electrical signal at room temperature…
We theoretically investigate the ultrafast terahertz(THz) properties of monolayer graphene. The analytical formulations of the photon carrier, electric polarization and optical current are obtained by solving the Bloch-equations in present…
Graphene is a promising material for ultrafast and broadband photodetection. Earlier studies addressed the general operation of graphene-based photo-thermoelectric devices, and the switching speed, which is limited by the charge carrier…
For future on-chip communication schemes, it is essential to integrate nanoscale materials with an ultrafast optoelectronic functionality into high-frequency circuits. The atomically thin graphene has been widely demonstrated to be suitable…
We propose the terahertz (THz) detectors based on field-effect transistors (FETs) with the graphene channel (GC) and the black-Arsenic (b-As) black-Phosphorus (b-P), or black-Arsenic-Phosphorus (b-As$_x$P$_{1-x}$) gate barrier layer. The…
We have investigated a THz detection scheme based on mixing of electrical signals in a voltage-dependent capacitance made out of suspended graphene. We have analyzed both coherent and incoherent detection regimes and compared their…
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…
We study broadband terahertz (THz) conductivity and ultrafast photoconductivity spectra in lithographically fabricated multilayer epitaxial graphene nanoribbons grown on C- face of 6H-SiC substrate. THz near-field spectroscopy reveals local…
Graphene is considered as a promising platform for detectors of high-frequency radiation up to the terahertz (THz) range due to graphene$'$s superior electron mobility. Previously it has been shown that graphene field effect transistors…
Graphene based photo-detecting has received great attentions and the performance of such detector is stretching to both ends of high sensitivity and ultra-fast response. However, limited by the current photo-gating mechanism, the price for…
Graphene-based photodetectors are promising new devices for high-speed optoelectronic applications. However, despite recent efforts, it is not clear what determines the ultimate speed limit of these devices. Here, we present measurements of…
We propose to utilize multiple-graphene-layer structures with lateral p-i-n junctions for terahertz (THz) and infrared (IR) photodetection and substantiate the operation of photodetectors based on these structures. Using the developed…
We propose an on-chip CMOS compatible graphene plasmonic photodetector based on the photo-thermoelectric effect (PTE) that occurs across an entire homogeneous graphene channel. The proposed photodetector incorporates the long-range…
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…