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Graphene is a very attractive material for broadband photodetection in hyperspectral imaging and sensing systems. However, its potential use has been hindered by tradeoffs between the responsivity, bandwidth, and operation speed of existing graphene photodetectors. Here, we present engineered photoconductive nanostructures based on gold-patched graphene nanoribbons, which enable simultaneous broadband and ultrafast photodetection with high responsivity. These nanostructures merge the advantages of broadband optical absorption, ultrafast photocarrier transport, and carrier multiplication in graphene nanoribbons with the ultrafast transport of photocarriers to the gold patches before recombination. Through this approach, high-responsivity operation is achieved without the use of bandwidth- and speed-limiting quantum dots, defect states, or tunneling barriers. We demonstrate high-responsivity photodetection from the visible to the infrared regime (0.6 A/W at 0.8 {mu}m and 11.5 A/W at 20 {mu}m) with operation speeds exceeding 50 GHz. Our results demonstrate an improvement of the response times by more than seven orders of magnitude and an increase in bandwidths of one order of magnitude compared to those of higher-responsivity graphene photodetectors based on quantum dots and tunneling barriers.
Graphene nanoribbons (GNRs) physisorbed on a Au(111) surface can be picked up, lifted at one end, and made slide by means of the tip of an atomic-force microscope. The dynamical transition from smooth sliding to multiple stick-slip regimes, the pushi
Silicon photonics is being extended from the near-infrared (near-IR) window of 1.3-1.5 {mu}m for optical fiber communications to the mid-infrared (mid-IR) wavelength-band of 2 {mu}m or longer for satisfying the increasing demands in many applications
Integrated photodetectors are essential components of scalable photonics platforms for quantum and classical applications. However, most efforts in the development of such devices to date have been focused on infrared telecommunications wavelengths.
Graphene integrated photonics provides several advantages over conventional Si photonics. Single layer graphene (SLG) enables fast, broadband, and energy-efficient electro-optic modulators, optical switches and photodetectors (GPDs), and is compatibl
A robust and reproducible preparation of self-standing nanoporous gold leaves (NPGL) is presented, with optical characterization and plasmonic behaviour analysis. Nanoporous gold (NPG) layers are tipically prepared as thin films on a bulk substrate.