TEPPE Frederic
Organisme : CNRS
Chargé de Recherche (HDR)
Autre(s) thème(s) de recherche ou rattachement(s) : - Spectroscopie Térahertz
Frederic.Teppe
univ-montp2.fr
0467144124
Bureau: 54.0, Bât: 13 - Site : Campus Triolet
Administration Locale:- Membre d'un pool d'experts
- Membre du conseil du laboratoire
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Domaines de Recherche: - Physique/Matière Condensée/Science des matériaux
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Dernieres productions scientifiques :
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Sub-threshold Attenuation of Terahertz Detection by Asymmetric Dual-Grating Gate HEMT Structures 
Auteur(s): COQUILLAT D. , Kurita K, Kobayashi K, TEPPE F., DIAKONOVA N., BUT D., Tohme L, Nouvel P, Blin S, Torres J, Pénarier A, Otsuji T, KNAP W.
Conference: International Workshop on Optical Terahertz Science and Technology (Kyoto, JP, 2013-04-01)
Actes de conférence: Extended Abstracts OTST 2013, vol. p.217 (2013)
Ref HAL: hal-00816663_v1
Résumé: The nonresonant detection of terahertz detectors based on asymmetric dual-grating-gate (A-DGG) high electron mobility transistors has been reported at both terahertz and sub-terahertz frequencies in several papers; but its behavior could not be fully understood in the range of the gate voltages close to and below the threshold voltage Vth. Two different contributions can attenuate the photoresponse u in the sub-threshold voltage region. The model developed in Ref. 3 showed that the gate leakage current suppresses the detector terahertz photoresponse in the sub-threshold region, leading to a nonresonant maximum in photoresponse versus gate dependence. While, in the model of Ref. 4, the detector loading effects were considered as responsible for the signal drop in the sub-threshold range. These effects are related to the voltage divider formed by input impedance of the measurement apparatus and the channel resistance of the detector which is exponentially increasing below threshold [4]. In the framework of the ANR-JST WITH project, we performed detailed studies of both the voltage u and the current i photoresponse of A-DGG devices. The photoresponse i was determined using the transfer characteristics measured with and without applied terahertz radiation. The measurements were carried out as a function of gate voltage and temperature (4 - 300 K), for incoming radiation frequencies of 292 and 655 GHz. As a result, we show that both effects are important and their relative contributions depend on gate voltage and temperature. We determine the separate contributions of the gate leakage current and the loading effect to the terahertz rectification signal in the sub-threshold region.
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Terahertz Rectification as Probe of quantum phenomena in Graphene
Auteur(s): COQUILLAT D., DIAKONOVA N., Ribeiro R, Goiran M, Poumirol J.M., Escoffier W., Raquet B, BUT D., BUZATU P., CONSEJO C., TEPPE F., KNAP W.
Conference: International Workshop on Optical Terahertz Science and Technology (Kyoto, JP, 2013-04-01)
Actes de conférence: Extended Abstracts OTST 2013, vol. p.144 (2013)
Ref HAL: hal-00816650_v1
Résumé: In this work, we undertake detailed studies of the mesoscopic rectification of an ac current at THz frequency induced by the incoming radiation for back-gated graphene field effect transistors. Using THz detection as a probe, we explore the nonlinear behavior of the quantum fluctuations and weak localization.
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Far infrared response of silicon nanowire arrays
Auteur(s): Fobelets K., Li C. b., COQUILLAT D., ARCADE P., TEPPE F.
(Article) Publié:
-RSC Advances, vol. 3 p.4434-4439 (2013)
Ref HAL: hal-00816474_v1
DOI: 10.1039/c3ra22880k
Résumé: The reflection, transmission and absorbance spectra of silicon nanowire arrays (NWAs), as a function of the length of the nanowires, are investigated in a wavelength range of 15 μm < λ < 200 μm, using Fourier transform infrared spectroscopy in vacuum. The NWAs are fabricated using metal-assisted electroless chemical etching. The wire length is varied between 20 μm and 140 μm, which is of the same order of magnitude as the wavelength, and their spectra are compared to bulk Si. At high frequencies the absorbance spectra of the NWAs show molecular resonances due to adsorption of molecules involved in the fabrication process but also due to the oxide quality that wraps the nanowires and changes as a function of nanowire length. Transmission characteristics show an increasing shift in absorption band edge towards the far infrared for longer wires and a transition from specular to diffuse reflection at a nanowire length of approximately 60 μm.
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Temperature dependence of terahertz radiation detection by field effect transistors
Auteur(s): Klimenko O., TEPPE F., KNAP W., Iniguez B, COQUILLAT D., Mityagin Y, DIAKONOVA N., Videlier H., Lime F, Marczewski J, Kucharski K
Conference: 37th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2012 (Wollongong, NSW, AU, 2012-09-23)
Actes de conférence: Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2012 37th International Conference on, vol. p.1 (2012)
Ref HAL: hal-00816972_v1
DOI: 10.1109/IRMMW-THz.2012.6380333
Résumé: We have measured the Terahertz photoresponse of three types of FETs as a function of the temperature, to study the change of the dominant current mechanism. For all of them we have compared the photoresponse with its DC transfer characteristics, which is directly proportional to the conductivity.
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Plasma wave detectors for Terahertz wireless communication and fast imaging applications
Auteur(s): TEPPE F., Blin S, COQUILLAT D., DIAKONOVA N., Tohme L, CHENAUD B., Hisatake S, Arakawa K, Torres J, CONSEJO C., Nouvel P, SOLIGNAC P., Penarier A, Nagatsuma T, KNAP W.
Conference: 37th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2012 (Wollongong, NSW, AU, 2012-09-23)
Actes de conférence: Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2012 37th International Conference on, vol. p.1 (2012)
Ref HAL: hal-00816950_v1
Résumé: We report on Terahertz wireless communications and fast imaging experiments at 300 GHz, using nanometer-sized transistors as detectors. The physical mechanism of the detection is related to the overdamped plasma waves in the transistor channel.
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