2020 |
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Komrakova S, Kovalyuk V, An P, Golikov A, Rybin M, Obraztsova E, et al. Effective absorption coefficient of a graphene atop of silicon nitride nanophotonic circuit. In: J. Phys.: Conf. Ser. Vol 1695.; 2020. 012135.
Abstract: In this paper, we demonstrate the results of a study of the optical absorption properties of graphene integrated with silicon nitride O-ring resonator. We fabricated an array of O-ring resonators with different graphene coverage area atop. By measuring the transmission spectra of nanophotonic devices with and without graphene, we calculated the effective absorption coefficient of the graphene on a rib silicon nitride waveguide.
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Matyushkin Y, Danilov S, Moskotin M, Belosevich V, Kaurova N, Rybin M, et al. Helicity-sensitive plasmonic terahertz interferometer. Nano Lett. 2020;20(10):7296–303.
Abstract: Plasmonic interferometry is a rapidly growing area of research with a huge potential for applications in the terahertz frequency range. In this Letter, we explore a plasmonic interferometer based on graphene field effect transistor connected to specially designed antennas. As a key result, we observe helicity- and phase-sensitive conversion of circularly polarized radiation into dc photovoltage caused by the plasmon-interference mechanism: two plasma waves, excited at the source and drain part of the transistor, interfere inside the channel. The helicity-sensitive phase shift between these waves is achieved by using an asymmetric antenna configuration. The dc signal changes sign with inversion of the helicity. A suggested plasmonic interferometer is capable of measuring the phase difference between two arbitrary phase-shifted optical signals. The observed effect opens a wide avenue for phase-sensitive probing of plasma wave excitations in two-dimensional materials.
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2018 |
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Fedorov G, Gayduchenko I, Titova N, Moskotin M, Obraztsova E, Rybin M, et al. Graphene-based lateral Schottky diodes for detecting terahertz radiation. In: Berghmans F, Mignani AG, editors. Proc. Optical Sensing and Detection V. Vol 10680. Spie; 2018. p. 30–9.
Abstract: Demand for efficient terahertz radiation detectors resulted in intensive study of the carbon nanostructures as possible solution for that problem. In this work we investigate the response to sub-terahertz radiation of graphene field effect transistors of two configurations. The devices of the first type are based on single layer CVD graphene with asymmetric source and drain (vanadium and gold) contacts and operate as lateral Schottky diodes (LSD). The devices of the second type are made in so-called Dyakonov-Shur configuration in which the radiation is coupled through a spiral antenna to source and top electrodes. We show that at 300 K the LSD detector exhibit the room-temperature responsivity from R = 15 V/W at f= 129 GHz to R = 3 V/W at f = 450 GHz. The DS detector responsivity is markedly lower (2 V/W) and practically frequency independent in the investigated range. We find that at low temperatures (77K) the graphene lateral Schottky diodes responsivity rises with the increasing frequency of the incident sub-THz radiation. We interpret this result as a manifestation of a plasmonic effect in the devices with the relatively long plasmonic wavelengths. The obtained data allows for determination of the most promising directions of development of the technology of nanocarbon structures for the detection of THz radiation.
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Gayduchenko I, Fedorov G, Titova N, Moskotin M, Obraztsova E, Rybin M, et al. Towards to the development of THz detectors based on carbon nanostructures. In: J. Phys.: Conf. Ser. Vol 1092.; 2018. 012039 (1 to 4).
Abstract: Demand for efficient terahertz radiation detectors resulted in intensive study of the carbon nanostructures as possible solution for that problem. In this work we investigate the response to sub-terahertz radiation of detectors with sensor elements based on CVD graphene as well as its derivatives – carbon nanotubes (CNTs). The devices are made in configuration of field effect transistors (FET) with asymmetric source and drain (vanadium and gold) contacts and operate as lateral Schottky diodes. We show that at 300K semiconducting CNTs show better performance up to 300GHz with responsivity up to 100V/W, while quasi-metallic CNTs are shown to operate up to 2.5THz. At 300 K graphene detector exhibit the room-temperature responsivity from R = 15 V/W at f = 129 GHz to R = 3 V/W at f = 450 GHz. We find that at low temperatures (77K) the graphene lateral Schottky diodes responsivity rises with the increasing frequency of the incident sub-THz radiation. We interpret this result as a manifestation of a plasmonic effect in the devices with the relatively long plasmonic wavelengths. The obtained data allows for determination of the most promising directions of development of the technology of nanocarbon structures for the detection of THz radiation.
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Gayduchenko IA, Fedorov GE, Moskotin MV, Yagodkin DI, Seliverstov SV, Goltsman GN, et al. Manifestation of plasmonic response in the detection of sub-terahertz radiation by graphene-based devices. Nanotechnol. 2018;29(24):245204 (1 to 8).
Abstract: We report on the sub-terahertz (THz) (129-450 GHz) photoresponse of devices based on single layer graphene and graphene nanoribbons with asymmetric source and drain (vanadium and gold) contacts. Vanadium forms a barrier at the graphene interface, while gold forms an Ohmic contact. We find that at low temperatures (77 K) the detector responsivity rises with the increasing frequency of the incident sub-THz radiation. We interpret this result as a manifestation of a plasmonic effect in the devices with the relatively long plasmonic wavelengths. Graphene nanoribbon devices display a similar pattern, albeit with a lower responsivity.
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Gayduchenko IA, Moskotin MV, Matyushkin YE, Rybin MG, Obraztsova ED, Ryzhii VI, et al. The detection of sub-terahertz radiation using graphene-layer and graphene-nanoribbon FETs with asymmetric contacts. In: Materials Today: Proc. Vol 5.; 2018. p. 27301–6.
Abstract: We report on the detection of sub-terahertz radiation using single layer graphene and graphene-nanoribbon FETs with asymmetric contacts (one is the Schottky contact and one – the Ohmic contact). We found that cutting graphene into ribbons a hundred nanometers wide leads to a decrease of the response to sub-THz radiation. We show that suppression of the response in the graphene nanoribbons devices can be explained by unusual properties of the Schottky barrier on graphene-vanadium interface.
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Matyushkin YE, Gayduchenko IA, Moskotin MV, Goltsman GN, Fedorov GE, Rybin MG, et al. Graphene-layer and graphene-nanoribbon FETs as THz detectors. In: J. Phys.: Conf. Ser. Vol 1124.; 2018. 051054.
Abstract: We report on detection of sub-THz radiation (129-430 GHz) using graphene based asymmetric field-effect transistor (FET) structures with different channel geometry: monolayer graphene, graphene nanoribbons. In all devices types we observed the similar trends of response on sub-THz radiation. The response fell with increasing frequency at room temperature, but increased with increasing frequency at 77 K. Our calculations show that the change in the trend of the frequency dependence at 77 K is associated with the appearance of plasma waves in the graphene channel. Unusual properties of p-n junctions in graphene are highlighted using devices of special geometry.
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2015 |
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Fedorov GE, Gaiduchenko IA, Golikov AD, Rybin MG, Obraztsova ED, Voronov BM, et al. Response of graphene based gated nanodevices exposed to THz radiation. In: EPJ Web of Conferences. Vol 103.; 2015. 10003 (1 to 2).
Abstract: In this work we report on the response of asymmetric graphene based devices to subterahertz and terahertz radiation. Our devices are made in a configuration of a field-effect transistor with conduction channel between the source and drain electrodes formed with a CVD-grown graphene. The radiation is coupled through a spiral antenna to source and top gate electrodes. Room temperature responsivity of our devices is close to the values that are attractive for commercial applications. Further optimization of the device configuration may result in appearance of novel terahertz radiation detectors.
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