Abstract-Room Temperature Amplification of Terahertz Radiation by Grating-Gate Graphene Structures

Stephane Boubanga-Tombet, Wojciech Knap, Deepika Yadav, Akira Satou, Dmytro B. But, Vyacheslav V. Popov, Ilya V. Gorbenko, Valentin Kachorovskii, Taiichi Otsuji

https://arxiv.org/abs/2003.09649

We report on experimental studies of terahertz (THz) radiation transmission through grating-gate graphene-channel transistor nanostructures and demonstrate room temperature THz radiation amplification stimulated by current-driven plasmon excitations. Specifically, with increase of the direct current (dc) under periodic charge density modulation, we observe a strong red shift of the resonant THz plasmon absorption, its complete bleaching, followed by the amplification and blue shift of the resonant plasmon frequency. Our results are, to the best of our knowledge, the first experimental observation of energy transfer from dc current to plasmons leading to THz amplification. We present a simple model allowing for the phenomenological description of the observed amplification phenomena. This model shows that in the presence of dc current the radiation-induced correction to dissipation is sensitive to the phase shift between THz oscillations of carrier density and drift velocity, and with increase of the current becomes negative, leading to amplification. The experimental results of this work as all obtained at room temperature, pave the way towards the new 2D plasmons based, voltage tuneable THz radiation amplifiers.

Abstract-Room-Temperature Amplification of Terahertz Radiation by Grating-Gate Graphene Structures

Stephane Boubanga-Tombet, Wojciech Knap, Deepika Yadav, Akira Satou, Dmytro B. But, Vyacheslav V. Popov, Ilya V. Gorbenko, Valentin Kachorovskii, and Taiichi Otsuji

https://journals.aps.org/prx/abstract/10.1103/PhysRevX.10.031004

We study terahertz (THz) radiation transmission through grating-gate graphene-based nanostructures. We report on room-temperature THz radiation amplification stimulated by current-driven plasmon excitation. Specifically, with an increase of the dc current under periodic charge density modulation, we observe a strong redshift of the resonant THz plasmon absorption, followed by a window of complete transparency to incoming radiation and subsequent amplification and blueshift of the resonant plasmon frequency. Our results are, to the best of our knowledge, the first experimental observation of energy transfer from dc current to plasmons leading to THz amplification. Additionally, we present a simple model offering a phenomenological description of the observed THz amplification. This model shows that in the presence of a dc current the radiation-induced correction to dissipation is sensitive to the phase shift between oscillations of carrier density and drift velocity. And, with an increasing current, the dissipation becomes negative, leading to amplification. The experimental results of this work, as all obtained at room-temperature, pave the way toward the new 2D plasmon-based, voltage-tunable THz radiation amplifiers.

• 
• 
• 
• 
• 
• 
• 

Abstract-Room temperature amplification of terahertz radiation by grating-gate graphene structures

Stephane Boubanga-Tombet, Wojciech Knap, Deepika Yadav, Akira Satou, Dmytro B. But, Vyacheslav V. Popov, Ilya V. Gorbenko, Valentin Kachorovskii, and Taiichi Otsuji

https://journals.aps.org/prx/accepted/52079K1dC0014a02342729a68f281fe27fbfc8908

We study terahertz (THz) radiation transmission through grating-gate graphene based nanostructures. We report on room temperature THz radiation amplification stimulated by current-driven plasmon excitation. Specifically, with increase of the dc current under periodic charge density modulation, we observe a strong red shift of the resonant THz plasmon absorption, followed by a window of complete transparency to incoming radiation, and subsequent amplification and blue shift of the resonant plasmon frequency. Our results are, to the best of our knowledge, the first experimental observation of energy transfer from dc current to plasmons leading to THz amplification. Additionally, we present a simple model offering phenomenological description of the observed THz amplification. This model shows that in the presence of dc current the radiation-induced correction to dissipation is sensitive to the phase shift between oscillations of carrier density and drift velocity. And with increasing current, the dissipation becomes negative, leading to amplification. The experimental results of this work, as all obtained at room temperature, pave the way towards the new 2D plasmons based, voltage tuneable THz radiation amplifiers.

Abstract-Room Temperature Amplification of Terahertz Radiation by Grating-Gate Graphene Structures

Stephane Boubanga-Tombet, Wojciech Knap, Deepika Yadav, Akira Satou, Dmytro B. But, Vyacheslav V. Popov, Ilya V. Gorbenko, Valentin Kachorovskii, Taiichi Otsuji

https://arxiv.org/abs/2003.09649

We report on experimental studies of terahertz (THz) radiation transmission through grating-gate graphene-channel transistor nanostructures and demonstrate room temperature THz radiation amplification stimulated by current-driven plasmon excitations. Specifically, with increase of the direct current (dc) under periodic charge density modulation, we observe a strong red shift of the resonant THz plasmon absorption, its complete bleaching, followed by the amplification and blue shift of the resonant plasmon frequency. Our results are, to the best of our knowledge, the first experimental observation of energy transfer from dc current to plasmons leading to THz amplification. We present a simple model allowing for the phenomenological description of the observed amplification phenomena. This model shows that in the presence of dc current the radiation-induced correction to dissipation is sensitive to the phase shift between THz oscillations of carrier density and drift velocity, and with increase of the current becomes negative, leading to amplification. The experimental results of this work as all obtained at room temperature, pave the way towards the new 2D plasmons based, voltage tuneable THz radiation amplifiers

Abstract-InP double heterojunction bipolar transistors for terahertz computed tomography

AIP Advances

Dominique Coquillat, Alexandre Duhant, Meriam Triki, Virginie Nodjiadjim, Agnieszka Konczykowska, Muriel Riet, Nina Dyakonova, Olivier Strauss, Wojciech Knap

(a) Schematic of the InP DHBT THz detector and read-out circuit connections. (b) Input characteristics IBE − VBE of the 3-finger device. Inset: SEM photograph of a 3-finger DHBT with 3 × 10 μm × 0.7 μm emitter area. (c) Photo-voltage ΔU (left hand scale) and area normalized voltage responsivity RmeasV$R_V^{meas}$ (right hand scale) as a function of frequency for VBE = 0.43 V.

https://aip.scitation.org/doi/abs/10.1063/1.5039331

We present experimental studies of terahertz radiation detection by InP double heterojunction based transistors. We analyze the relation between their static characteristics and the experimentally determined voltage and current responsivities, showing importance of internal device parasitic capacitances and the external circuit loading effects. Finally, we demonstrate the use of these transistors for terahertz radiation computed tomography leading to 3D visualization of concealed objects. Our results pave the way towards wide use of heterojunction based transistors for terahertz imaging.

Abstract-Terahertz Light Amplification by Current-Driven Plasmon Instabilities in Graphene

Stephane Boubanga-Tombet, Deepika Yadav, Wojciech Knap, Vyacheslav V. Popov, and Taichii Otsuji

http://www.etoponline.org/abstract.cfm?uri=CLEO_SI-2018-SW4D.4

This paper reports on room-temperature frequency tunable terahertz light amplification by current-driven plasmon instabilities produced in a graphene metasurface implemented in an asymmetric dual-grating-gate graphene field effect transistor.

© 2018 The Author(s)

Abstract-Black-Phosphorus Terahertz Photodetectors

Leonardo Viti, Jin Hu, Dominique Coquillat, Wojciech Knap, Alessandro Tredicucci, Antonio Politano, Miriam Serena Vitiello

https://arxiv.org/abs/1805.00735

The discovery of graphene and the related fascinating capabilities have triggered an unprecedented interest in inorganic two-dimensional (2D) materials. Despite the impressive impact in a variety of photonic applications, the absence of energy gap has hampered its broader applicability in many optoelectronic devices. The recent advance of novel 2D materials, such as transition-metal dichalcogenides or atomically thin elemental materials, (e.g. silicene, germanene and phosphorene) promises a revolutionary step-change. Here we devise the first room-temperature Terahertz (THz) frequency detector exploiting few-layer phosphorene, e.g., a 10 nm thick flake of exfoliated crystalline black phosphorus (BP), as active channel of a field-effect transistor (FET). By exploiting the direct band gap of BP to fully switch between insulating and conducting states and by engineering proper antennas for efficient light harvesting, we reach detection performance comparable with commercial detection technologies, providing the first technological demonstration of a phosphorus-based active THz device.

AbstractTHz Detection and Imaging using Graphene Ballistic Rectifiers

Gregory Hunter Auton, Dmytro But, jiawei Zhang, Ernie W. Hill, Dominique Coquillat, Christophe Consejo, Philippe Nouvel, Wojciech Knap, Luca Varani, Frederic Teppe, Jeremie Torres, and Aimin Song

http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.7b03625?journalCode=nalefd

A graphene ballistic rectifier is used in conjunction with an antenna to demonstrate a rectenna as a terahertz (THz) detector. A small-area (<1 μm2) local gate is used to adjust the Fermi level in the device to optimise the output while minimising the impact on the cut-off frequency. The device operates in both n- and p-type transport regimes and shows a peak extrinsic responsivity of 764 V/W and a corresponding noise equivalent power of 34 pW Hz-1/2 at room temperature with no indications of a cut-off frequency up to 0.45 THz. The device also demonstrates a linear response for more than three orders of magnitude of input power due to its zero threshold voltage, quadratic current-voltage characteristics and high saturation current. Finally, the device is used to take an image of an optically opaque object at 0.685 THz, demonstrating potential in both medical and security imaging applications.

US Patent-Impedance adaptation in a THz detector

United States Patent 9614116
Inventors:

Le Bars, Philippe (Thorigne Fouillard, FR) 
Sahyoun, Walaa (Rennes, FR) 
Knap, Wojciech (Saint-Gely-du-Fesc, FR) 
Diakonova, Nina (Montpellier, FR) 
Coquillat, Dominique (Prades-le-Lez, FR) 

http://www.freepatentsonline.com/9614116.html

At least one electronic device, system and method of manufacturing an electromagnetic wave detector are provided herein. The electronic device for receiving at least one electromagnetic wave of a given frequency may comprise at least one first field effect transistor, and at least one antenna configured to receive the at least one electromagnetic wave and connected to a gate of the at least one first field effect transistor, wherein a length of the gate is in a same order of magnitude as an oscillation length of an oscillation regime of the at least one first field effect transistor at the given frequency, and a width of the gate is such that an impedance presented by the at least one first field effect transistor in the oscillation regime is adapted to an impedance of the at least one antenna.

Abstract-Wide modulation bandwidth terahertz detection in 130 nm CMOS technology

Shamsun Nahar1, Marwah Shafee2, Stéphane Blin3, Annick Pénarier3, Philippe Nouvel3, Dominique Coquillat4, Amr M.E. Safwa2, Wojciech Knap4a and Mona M. Hella1

1 ECSE Department, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
2 ECE Department, Ain Shams University, 11566 Cairo, Egypt
3 Institut d’électronique et des Systèmes, UMR 5214 CNRS-Université de Montpellier, 34095 Montpellier, France
4 Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-Université de Montpellier, 34095 Montpellier, France 

a e-mail: knap.wojciech@gmail.com 

http://www.epjap.org/articles/epjap/abs/2016/11/ap160302/ap160302.html

Design, manufacturing and measurements results for silicon plasma wave transistors based wireless communication wideband receivers operating at 300 GHz carrier frequency are presented. We show the possibility of Si-CMOS based integrated circuits, in which by: (i) specific physics based plasma wave transistor design allowing impedance matching to the antenna and the amplifier, (ii) engineering the shape of the patch antenna through a stacked resonator approach and (iii) applying bandwidth enhancement strategies to the design of integrated broadband amplifier, we achieve an integrated circuit of the 300 GHz carrier frequency receiver for wireless wideband operation up to/over 10 GHz. This is, to the best of our knowledge, the first demonstration of low cost 130 nm Si-CMOS technology, plasma wave transistors based fast/wideband integrated receiver operating at 300 GHz atmospheric window. These results pave the way towards future large scale (cost effective) silicon technology based terahertz wireless communication receivers.

Abstract-Terahertz imaging of Landau levels in HgTe-based topological insulators

Aleksandr M. Kadykov1,2, Jeremie Torres3, Sergey S. Krishtopenko1,2,Christophe Consejo1, Sandra Ruffenach1, Michal Marcinkiewicz1, Dmytro But1, Wojciech Knap1,4, Sergey V. Morozov2,5, Vladimir I. Gavrilenko2,5,Nikolai N. Mikhailov6,7, Sergey A. Dvoretsky6 and Frederic Teppe1,a)

1 Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS–Université de Montpellier, Montpellier, France

2 Institute for Physics of Microstructures, Russian Academy of Sciences, GSP-105, 603950 Nizhny Novgorod, Russia

3 Institut d'Electronique et des Systèmes (IES), UMR 5214 CNRS–Université de Montpellier, Montpellier, France

4 Institute of High Pressure Institute Physics, Polish Academy of Sciences, 01-447 Warsaw, Poland

5 Lobachevsky State University of Nizhny Novgorod, 603950 Nizhny Novgorod, Russia

6 Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, pr. Akademika Lavrent'eva 13, 630090 Novosibirsk, Russia

7 Novosibirsk State University, 630090 Novosibirsk, Russia

a) Electronic mail: frederic.teppe@umontpellier.fr

http://scitation.aip.org/content/aip/journal/apl/108/26/10.1063/1.4955018

Appl. Phys. Lett. 108, 262102 (2016); http://dx.doi.org/10.1063/1.4955018

We report on sub-terahertz photoconductivity under the magnetic field of a two dimensional topologicalinsulator based on HgTe quantum wells. We perform a detailed visualization of Landau levels by means of photoconductivity measured at different gate voltages. This technique allows one to determine a criticalmagnetic field, corresponding to topological phase transition from inverted to normal band structure, even in almost gapless samples. The comparison with realistic calculations of Landau levels reveals a smaller role of bulk inversion asymmetry in HgTe quantum wells than it was assumed previously.

Abstract-Heterostructured hBN-BP-hBN Nanodetectors at Terahertz Frequencies

http://onlinelibrary.wiley.com/doi/10.1002/adma.201601736/abstract

By reassembling the thin isolated atomic planes of hexagonal borum nitride (hBN) with a few layer phosphorene (black phosphorus BP), hBN/BP/hBN heterostructures were mechanically stacked to devise high efficiency THz photodetectors operating in the 0.3–0.65 THz range, from 4K to 300K, with a record signal-to-noise ratio of 20000.