Asymmetric Two-Terminal Graphene Detector for Broadband Radiofrequency Heterodyne- and Self-Mixing

Abstract

Graphene, a single atomic layer of covalently bonded carbon atoms, has been investigated intensively for optoelectronics and represents a promising candidate for high-speed electronics. Here, we present a microwave mixer constructed as an asymmetrically contacted two-terminal graphene device based on the thermoelectric effect. We report a 50 GHz (minimum) mixer bandwidth as well as 130 V/W (163 mA/W) extrinsic direct-detection responsivity. Anomalous second-harmonic generation due to self-mixing in our graphene detector is also observed. Careful investigation of the responsivity from four different approaches gives consistent results, confirming the exceptional performance of our zero-bias device operating at room temperature. The 50 GHz bandwidth indicates an extremely fast response time and our experimental results represent an encouraging advance toward practical graphene microwave devices with anticipated future applications extended through millimeter wave and terahertz frequencies.

Decoupling Chemically Active 2D Molecular Overlayers from the Substrate: Chlorophenyl Porphyrins on Graphene/Ir(111)

“…Over the past few years, a significant number of scientific publications and patents have paved the way toward the commercial realization of graphene-based electronic devices, including spin filters and giant magnetoresistance devices, − tunable terahertz devices, − or high-frequency large-bandwidth electronics, − to mention just a few. In addition, molecular self-assembly has emerged as a feasible and scalable route toward the realization of graphene–molecule devices with tailored properties to expand the scope of their magnetic/electronic applications. − Magnetic porphyrin molecules covalently bonded or “wired” to graphene nanoribbons have been proposed as potential molecular spintronic systems.…”

Large Responsivity of Graphene Radiation Detectors with Thermoelectric Readout: Results of Simulations

“…The graphene radiation detectors promise to be fast and sensitive devices in a broad frequency band from sub-THz-to infrared spectrum of electromagnetic radiation, operational from ambient [1]-to cryo temperatures [2]. A negligibly small thermal mass of a typical graphene radiation absorber guarantees a very short response time of the detector [3][4][5][6][7][8].…”

“…Among practical devices reported in the literature, graphene detectors with TEP readout experimentally demonstrated quite high responsivity 100 − 1000 V/W and low noiseequivalent power N EP ∼ 20 − 200 pW/ √ Hz [4,7,20,21]. The responsivity in detectors with TEP readout is usually 10 − 100 times higher than in those based on graphene field-effect transistors (GFET's), unless GFET's have very high mobility [12].…”

Graphene-Based Optoelectronic Mixer Device for Time-of-Flight Distance Measurements for Enhanced 3D Imaging Applications

“…Although mixing of two optical or two electrical signals has already been demonstrated in graphene as well as optoelectronic mixing at modulation frequencies above 65 GHz , in highly optimized device structures, previous articles only mention 3D imaging to be a potential application lacking further demonstration.…”

“…Furthermore, the linear dispersion relation of graphene allows for an unlimited choice of illumination wavelengths and thus does not restrict applications due to light or laser safety limitations. 23 Although mixing of two optical 24 or two electrical signals 25 has already been demonstrated in graphene as well as optoelectronic mixing at modulation frequencies above 65 GHz 26,27 in highly optimized device structures, previous articles only mention 3D imaging to be a potential application lacking further demonstration.…”