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A 61.2-dBΩ, 100 Gb/s Ultra-Low Noise Graphene TIA over D-Band Performance for 5G Optical Front-End Receiver J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-14 Pradeep Gorre, R. Vignesh, Hanjung Song, Sandeep Kumar
This work reports in first time a 100-Gb/s, ultra-low noise, variable gain multi-stagger tuned transimpedance amplifier (VGMST-TIA) over the D-band performance. The whole work is binding into two phases. The first phase involves the modeling and characterization of graphene field-effect transistor (GFET) with an optimized transition frequency of operation. While in the second phase, a TIA design employs
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Mechanical Tuning of the Terahertz Photonic Bandgap of 3D-Printed One-Dimensional Photonic Crystals J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-08 Serang Park, Brandon Norton, Glenn D. Boreman, Tino Hofmann
Mechanical tuning of a 3D-printed, polymer-based one-dimensional photonic crystal was demonstrated in the terahertz spectral range. The investigated photonic crystal consists of 13 alternating compact and low-density layers and was fabricated through single-step stereolithography. While the compact layers are entirely polymethacrylate without any intentional internal structures, the low-density layers
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Selective Laser Melting Process of Al–Based Pyramidal Horns for the W-Band: Fabrication and Testing J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-08 L. Lamagna, A. Paiella, S. Masi, L. Bottini, A. Boschetto, F. Veniali
In the context of exploring the possibility of using Al-powder Selective Laser Melting to fabricate horn antennas for astronomical applications at millimeter wavelengths, we describe the design, the fabrication, the mechanical characterization, and the electromagnetic performance of additive manufactured horn antennas for the W-band. Our aim, in particular, is to evaluate the performance impact of
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Study on a Depressed Collector for a 75 GHz Low-Voltage Compact Gyrotron for Industrial Application J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-07 Dun Lu, Wenjie Fu, Xiaotong Guan, Tongbin Yang, Yang Yan
The low-voltage compact gyrotron is suitable for industrial applications. However, the beam-wave interaction efficiency is low in conventional low-voltage gyrotron. To improve the whole tube efficiency, a compact depressed collector is introduced in developing a 75 GHz low-voltage compact gyrotron. The compact depressed collector is directly connected to the output waveguide. It is grounded and isolated
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Compact Highly Directive MIMO Vivaldi Antenna for 5G Millimeter-Wave Base Station J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-07 Rania H. Elabd, Haythem H. Abdullah, Mohamed Abdelazim
In this paper, a novel design for a 5G base station (BS) antenna is proposed. The proposed antenna consists of two orthogonally polarized antennas. The two antennas are modified compact Vivaldi antennas operating in the two recommended 5G operating bands; 28 and 38 GHz with measured impedance bandwidth of 26.5–40 GHz. The orthogonality of the two antennas allows the use of two antennas on the same
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Broadband Rotary Joint Concept for High-Power Radar Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-05 Daniel Haas, Manfred Thumm, John Jelonnek
To allow antenna movements in azimuth and elevation in high-power radar applications, rotary joints are essential. They allow the rotation of a transmission line and therefore are important transmission line components. In the present paper, a broadband rotary joint concept for high-power W-band radar applications is proposed. To avoid a twist of the polarization plane of a linearly polarized mode
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Developments in Terahertz Ellipsometry: Portable Spectroscopic Quasi-Optical Ellipsometer-Reflectometer and Its Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-05 Alla Belyaeva, Alexey Galuza, Ivan Kolenov, Sergey Mizrakhy
The paper presents a new instrument—a portable spectroscopic quasi-optical (QO) THz ellipsometer-reflectometer (SQOTER). It combines two independent experimental techniques: THz ellipsometry and reflectometry. SQOTER is based on the hollow dielectric beamguide and beamguide components as a QO transmission line. This ultra-broadband line provides operation of the setup within 0.1…1 THz frequency range
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A 183-GHz FMCW Transceiver Module for Wireless Fuse Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-04 Changfei Yao, Xiaoxiao Feng, Jinhai Sun, Feng Huang
This paper presents the design, construction, and testing of a 183-GHz FMCW transceiver module for wireless fuse applications. The transmitter consists of a square-triangle wave converter, a Ku-band VCO, a 91.5-GHz × 2 × 3 multiplying and amplifying chain, a 10-dB multi-hole directional coupler, and a 183-GHz frequency doubler. For the multiplying chain, the generated 91.5-GHz signal power is partly
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Influence of an External Signal with Harmonic or Stepwise-Modulated Parameters on the High-Power Gyrotron Operation J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-04 Vladimir L. Bakunin, Gregory G. Denisov, Yulia V. Novozhilova
Nonlinear dynamics of a gyrotron with high-order operating mode, driven by an external signal with harmonic or stepwise modulation of its parameters or by two monochromatic signals, was studied theoretically. Conditions for locking and control of the radiation frequency were found. Exit from the locking regime is accompanied by the beats of the operating mode or excitation of spurious modes. Simulations
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Mode Discrimination by Lossy Dielectric Rods in Cavities of Second-Harmonic Gyrotrons J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2021-01-04 Vitalii I. Shcherbinin, Konstantinos A. Avramidis, Manfred Thumm, John Jelonnek
The influence of a coaxial dielectric rod on eigenvalues, ohmic losses, transverse field structure, and beam-wave coupling coefficients is investigated for TE modes of a gyrotron cavity. It is shown that such dielectric insert, when made from a moderate-loss material, results in strong attenuation of all cavity modes, with the exception of those having caustic radii much larger than the insert radius
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A Modular MIMO Millimeter-Wave Imaging Radar System for Space Applications and Its Components J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-11-26 Michael Hrobak, Karsten Thurn, Jochen Moll, Maruf Hossain, Amit Shrestha, Thualfiqar Al-Sawaf, Dimitri Stoppel, Nils G. Weimann, Adam Rämer, Wolfgang Heinrich, Javier Martinez, Martin Vossiek, Tom K. Johansen, Viktor Krozer, Marion Resch, Jürgen Bosse, Michael Sterns, Kai Loebbicke, Stefan Zorn, Mohamed Eissa, Marco Lisker, Frank Herzel, Robert Miesen, Klaus Vollmann
This article presents the design and prototyping of components for a modular multiple-input-multiple-output (MIMO) millimeter-wave radar for space applications. A single radar panel consists of 8 transmitters (TX) and 8 receivers (RX), which can be placed several times on the satellite to realize application-specific radar apertures and hence different cross-range resolutions. The radar chirp signals
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Excitation of Electromagnetically Induced Transparency Effect in Asymmetrical Planar Terahertz Toroidal Dipole Metasurfaces J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-11-25 Song Wang, Shuang Wang, Xiaoli Zhao, Jianyu Zhu, Quan Li, Tai Chen
We proposed and fabricated J-shaped planar structure metasurfaces to achieve excitation of dual-frequency toroidal dipole resonances simultaneously, which results in electromagnetically induced transparency effect in the terahertz band. The mutual coupling of two asymmetric J-shaped metal rings in the metasurface units excites low-frequency and high-frequency toroidal dipole resonances, and a transparent
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Investigation of the Correlations between Amino Acids, Amino Acid Mixtures and Dipeptides by Terahertz Spectroscopy J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-11-23 Yujing Bian, Xun Zhang, Zhenqi Zhu, Xiaodong Wu, Xiang Li, Bin Yang
Terahertz (THz) spectroscopy is regarded as a professional technology to probe collective molecular vibrational modes and intensity of bio–molecules, which is potential to analyze amino acids and short peptides. In this study, THz spectroscopy is utilized to investigate the correlations of glycine (Gly), Serine (Ser), amino acid mixtures of Gly/Ser, and dipeptides (GS and SG) in the frequency range
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THz Spectroscopic Decomposition and Analysis in Mixture Inspection Using Soft Modeling Methods J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-11-23 Chen Xie, Zhangwei Huang, Yiwen E, Xi-Cheng Zhang, Xusheng Kang, Yehao Ma, Pingjie Huang, Guangxin Zhang
At present, the terahertz time-domain spectroscopic information of each component in multi-composition compounds detection is comprehensively combined. The lower resolution level of mixed spectra has posed many difficulties in signal analysis due to the overlapping characteristic information in the mixed ones. In this paper, to compare the performances of Nonnegative Matrix Factorization (NMF), Self-modeling
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Wideband Circularly Polarized Magnetoelectric Dipole Array Using T E 340 -Mode Cavity and Sequential Rotation Feed-Network at 60 GHz J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-11-10 Zihang Qi, Yuefang Zhu, Xiuping Li
In this paper, a 4 × 4 60-GHz circularly polarized (CP) magnetoelectric (ME) dipole array based on TE340-mode substrate integrated cavity (SIC) and sequential rotation feed-network (SRFN) is proposed. The ME dipole array is constructed by 3 printed circuit board (PCB) layers with its assembled size of 21 × 23 × 2.4 mm3. The top layer is the radiation layer with 2 × 2 subarrays. The second layer includes
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Novel 500-GHz Band Waveguide Stepped Septum-Type Circular Polarizer with a New High-Accuracy and Very Small Waveguide Flange J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-10-29 Yutaka Hasegawa, Hiroyuki Maezawa, Hideo Ogawa
A new waveguide stepped septum-type circular polarizer (SST-CP) was developed to operate in the 500-GHz band for radio astronomical and planetary atmospheric observations. In a previous study, we developed a practical SST-CP for the 230-GHz band. However, several issues prevent this device being easily scaled down to the 500-GHz band, such as manufacturing dimensional errors and waveguide flange position
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Phase Measurements of a 140-GHz Confocal Gyro-Amplifier J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-10-27 Guy Rosenzweig, Sudheer K. Jawla, Julian F. Picard, Michael A. Shapiro, Richard J. Temkin
The phase stability of a 140-GHz, 1-kW pulsed gyro-amplifier system and the phase dependence on the cathode voltage were experimentally measured. To optimize the measurement precision, the amplifier was operated at 47 kV and 1 A, where the output power was ∼30 W. The phase was determined to be stable both pulse-to-pulse and during each pulse, so far as the cathode voltage and electron beam current
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Study on on-Chip Antenna Design Based on Metamaterial-Inspired and Substrate-Integrated Waveguide Properties for Millimetre-Wave and THz Integrated-Circuit Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-10-26 Mohammad Alibakhshikenari, Bal S. Virdee, Ayman Abdulhadi Althuwayb, Sonia Aïssa, Chan H. See, Raed A. Abd-Alhameed, Francisco Falcone, Ernesto Limiti
This paper presents the results of a study on improving the performance parameters such as the impedance bandwidth, radiation gain and efficiency, as well as suppressing substrate loss of an innovative antenna for on-chip implementation for millimetre-wave and terahertz integrated-circuits. This was achieved by using the metamaterial and the substrate-integrated waveguide (SIW) technologies. The on-chip
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Self-Consistent Electro-Thermal Approach for Terahertz Frequency Multiplier Design J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-10-16 Carlos G. Pérez-Moreno, Jesús Grajal
Solid-state sources consisting of cascaded Schottky diode-based frequency multipliers are commonly used to generate power at millimeter and submillimeter wave bands. In order to achieve increasing power at those frequencies, first-stage frequency multipliers have to handle a large amount of input power and generate enough output power to drive higher frequency multiplication stages. To that end, an
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Correction to: Exploring the Reliability of DFT Calculations of the Infrared and Terahertz Spectra of Sodium Peroxodisulfate J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-10-02 Andrew D. Burnett, John Kendrick
This article is intended for inclusion in the Special Issue on Interpretation of Solid-State Terahertz Spectra.
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Magnetron-Injection Gun with Increased Current for Frequency Tunable Medium Power Sub-THz Gyrotron J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-26 V. N. Manuilov, A. E. Fedotov, I. V. Zotova, R. M. Rozental, T. Idehara, S. Mitsudo, M. Yu. Glyavin
A magnetron-injection gun able to provide very high ratio tj≈ 0.5 of the beam current to the Langmuir current has been designed, while maintaining good enough quality and stability of a formed helical electron beam. The specific feature of the gun is the shape of the cathode with two singular points of the electric field distribution which ensure close to uniform electric field profile within the emitter
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Sub-Terahertz Complex Permittivity Measurement Method Using Cavity Switches J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-17 Maxim L. Kulygin, Ilya A. Litovsky
New method of measurement of dielectric constant and loss tangent for small samples of lossy dielectrics, including plain semiconductors, using non-oversized resonators being parts of the recently developed cavity switches for sub-terahertz bands is proposed. Strong influence of the tangent loss value to the Q-factor of the resonator is calculated and observed in experiments. A simple monosemantic
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Correction to: “A Compact Two-Frequency Notch Filter for Millimeter Wave Plasma Diagnostics” J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-16 D. Wagner, W. Kasparek, F. Leuterer, F. Monaco, T. Ruess, J. Stober, M. Thumm
The original article contains mistakes specifically in the presentation of references.
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Modern Dielectric Materials for Output Windows of High-Power Microwave and Terahertz Sources J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-16 E. A. Serov, V. V. Parshin, K. V. Vlasova, A. I. Makarov
Analysis of dielectric properties of several materials, BN, AlN with BN additive, crystalline quartz, MgAl2O4 spinel, 6H-SiC in the millimeter and submillimeter (terahertz) ranges, is presented. Basing on the experimentally measured dielectric losses of these materials and on their thermal and mechanical properties, we made a calculation to estimate the maximal achievable output power that can be transmitted
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Terahertz Conductivity Analysis for Highly Doped Thin-Film Semiconductors J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-15 Aleksander M. Ulatowski, Laura M. Herz, Michael B. Johnston
The analysis of terahertz transmission through semiconducting thin films has proven to be an excellent tool for investigating optoelectronic properties of novel materials. Terahertz time-domain spectroscopy (THz-TDS) can provide information about phonon modes of the crystal, as well as the electrical conductivity of the sample. When paired with photoexcitation, optical-pump-THz-probe (OPTP) technique
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Waveguide-Type Multiplexer for Multiline Observation of Atmospheric Molecules using Millimeter-Wave Spectroradiometer J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-11 Taku Nakajima, Kohei Haratani, Akira Mizuno, Kazuji Suzuki, Takafumi Kojima, Yoshinori Uzawa, Shin’ichiro Asayama, Issei Watanabe
In order to better understand the variation mechanism of ozone abundance in the middle atmosphere, the simultaneous monitoring of ozone and other minor molecular species, which are related to ozone depletion, is the most fundamental and critical method. A waveguide-type multiplexer was developed for the expansion of the observation frequency range of a millimeter-wave spectroradiometer, for the simultaneous
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Investigation on a Ka Band Diamond-Supported Meander-Line SWS J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-09-01 Zhanliang Wang, Liangxin Su, Zhaoyun Duan, Qiang Hu, Huarong Gong, Zhigang Lu, Jinjun Feng, Shifeng Li, Yubin Gong
The microstrip meander-line traveling wave tube (TWT) is a kind of small sized, low voltage, low cost, and easy to fabricate TWT. It is an attractive choice for many applications, such as communication systems, phased array radars, security detectors, and electronic counter measure (ECM) instruments. In this paper, a Ka band U-shape meander-line slow wave structure (SWS) supported by a diamond rod
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Design and Realization of a Band Pass Filter at D-band Using Gap Waveguide Technology J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-08-29 Jose Luis Vazquez-Roy, Eva Rajo-Iglesias, Giacomo Ulisse, Viktor Krozer
Gap waveguide technology is particularly attractive for the design of passive elements in mm-wave systems. Recently, the so-called zero-gap implementation has proved to be very robust to manufacturing tolerances, while at the same time keeping the low loss associated to the contactless standard gap waveguide. In this paper, a Chebyshev filter working at 145 GHz based on this idea and intended to be
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Characterization of Varnish Ageing and its Consequences on Terahertz Imagery: Demonstration on a Painting Presumed of the French Renaissance J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-08-29 Q. Cassar, C. L. Koch-Dandolo, J. P. Guillet, M. Roux, F. Fauquet, J. B. Perraud, P. Mounaix
We report on advance developments of terahertz system data analysis for measuring the thicknesses of multiple films for non-contact control in heritage science. We provide the analysis of time-domain data regarding the measurements conducted on a French Renaissance painting realized on a copper substrate. The piece of art is made of a varnish layer deposited on the different painting layers. We specifically
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Structure-Simplified Resonant-Tunneling-Diode Terahertz Oscillator Without Metal-Insulator-Metal Capacitors J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-08-29 Ta Van Mai, Yusei Suzuki, Xiongbin Yu, Safumi Suzuki, Masahiro Asada
We propose and fabricate a novel structure-simplified resonant tunneling diode (RTD) terahertz (THz) oscillator without metal-insulator-metal (MIM) capacitors. In conventional RTD THz oscillators, the DC and RF circuits are separated by MIM capacitors. In the proposed oscillator, the DC-to-RF separation is based on the difference between the impedances of the antenna and biasing wire inductances in
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WR-3 Band Waveguide Filter Tolerance Analysis and Surface Metallization Comparison J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-08-22 Daniel Miek, Fynn Kamrath, Patrick Boe, Michael Höft
In this paper, a fifth-order WR-3 band waveguide filter with two transmission zeros (TZs) is presented. The design process is described and manufacturing issues are addressed. The filter is designed to fulfill a center frequency of 237.9 GHz and a fractional bandwidth of 2.64%. Three identical filters are manufactured with the classical computerized numerical control (CNC) milling technique in order
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Theoretical Exploration of Terahertz Single-Photon Detection and Imaging by Nonlinear Optical Frequency Up-Conversion J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-08-12 Xiaoqin Yin, Junliang Liu, Shuzhen Fan, Yongfu Li, Zhaojun Liu, Xian Zhao, Jiaxiong Fang
Terahertz single-photon detection and imaging have attracted full attention recently. Nonlinear optical frequency up-conversion is a promising technique that can be expected to satisfy this demand thanks to its high sensitivity and fast response. In this paper, theoretical analysis and numerical calculations based on the organic salt 4′-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST) crystal
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Demonstration of W-Band 30-W Continuous-Wave Folded Waveguide Traveling Wave Tube with Lowered Operation Voltage and Improved Gain Flatness J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-30 Fei Li, Liu Xiao, Tianjun Ma, Yuhui Sun, Jiandong Zhao, Jian Wang, Cha Gao, Linlin Cao, Mingguang Huang
We have demonstrated and developed a W-band 30 W continuous-wave folded waveguide traveling wave tube (CW FWTWT) with 13.5-kV operation voltage and 4.8 dB gain flatness. In this paper, we quantitatively study the relationship between operating voltage and the key geometric dimensions of a folded waveguide, which is the key to the design of the low-voltage TWT. In addition, problems of improving beam
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MEMS Slow-Wave CPW Phase Shifter for mm-Wave Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-27 Gustavo P. Rehder, Robert G. Bovadilla, Franz S. Bedoya, Bruno Reig, Cedric Dehos, Ariana L. C. Serrano, Victoria Nasserddine, Philippe Ferrari
MEMS-based phase shifters show the best performance in terms of figure of merit, but their footprints are usually large and it is difficult to achieve several bits. This paper demonstrates a miniaturized phase shifter based on slow-wave CPW and MEMS that occupy 0.47 mm2. A total phase shift of 152° was obtained with a maximum insertion loss of 3 dB, resulting in a figure of merit of 50°/dB at 60 GHz
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Analytical Uncertainty Evaluation of Material Parameter Measurements at THz Frequencies J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-24 Alireza Kazemipour, Michael Wollensack, Johannes Hoffmann, Martin Hudlička, See-Khee Yee, Jürg Rüfenacht, Daniel Stalder, Gregory Gäumann, Markus Zeier
Material parameter extraction algorithms are studied and simplified both for transmission-reflection and transmission-only methods. The simplified relations, which are closed-form in some cases, are analyzed to establish the uncertainty sensitivity coefficients and therefore, to clarify the main uncertainty contributions and reduce the systematic and random errors. Simple closed-form expressions presented
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Fast Terahertz Spectroscopic Holographic Assessment of Optical Properties of Diabetic Blood Plasma J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-18 Maksim S. Kulya, Evgeniy L. Odlyanitskiy, Quentin Cassar, Ilia A. Mustafin, Valery N. Trukhin, Polina G. Gavrilova, Dmitry V. Korolev, Yulia A. Kononova, Nikolay S. Balbekin, Patrick Mounaix, Jean-Paul Guillet, Nikolay V. Petrov, Olga A. Smolyanskaya
A new method for diagnosis of diabetes mellitus is proposed, which uses for measurement a lyophilized blood plasma sample prepared in the form of a pellet. The paper develops a methodology for fast spectroscopic measurements of such pellets with terahertz pulse time-domain holography. For that reason, blood plasma pellets were experimentally measured by terahertz time-domain spectroscopy system in
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Waveguide ASK Modulator Using Switchable FSS J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-16 Ghaffer Iqbal Kiani, Mohammed Abdullah Hussaini
A waveguide modulator using switchable frequency selective surface (FSS) for amplitude shift keying modulation (ASK) at super high frequency (SHF) has been presented. The FSS consists of rectangular loop aperture elements with two PIN diodes at 180∘ intervals on every unit cell across the aperture. A minimum transmission isolation of 30 dB has been achieved at resonance frequency when the diodes are
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Experimental Measurement of Temperature-Dependent Thermo-optical Parameters of Different Types of Olive Oil Using Terahertz Time-Domain Spectroscopy J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-14 Muhammad Mumtaz, M. Ahsan Mahmood, Arslan Shahzad, Sabih D Khan, M. Aslam Zia, Mushtaq Ahmed, Izhar Ahmad
Terahertz time-domain spectroscopy has been used for the characterization of different types of olive oil, such as extra virgin, pure, extra light, and pomace olive oils. Temperature-dependent refractive indices and absorption coefficients have been measured in 0.2–1.6 THz spectral-frequency range. Temperature-dependent Sellmeier coefficients and thermo-optic coefficients of these oil samples have
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Millimeter-Wave Complex Permittivity of Silica/Alumina-Filled Epoxy-Molding Compounds J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-14 Michael P. McGarry, Enis Tuncer, Mark Lee
Composite materials made of micron-sized oxide particle fillers in an epoxy resin matrix that can be molded into desired shapes are widely used for packaging radiofrequency and microwave-integrated circuits (ICs). To potentially employ these materials with millimeter-wave ICs (MMICs), quantitative knowledge of the composites’ dielectric properties across a broad millimeter-wave band is necessary. Here
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Ultrabroadband and Low-Dispersion Multiple-Joint Transmission-Line for Terahertz Region J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-14 Hideaki Kitahara, Masanori Hangyo, Masahiko Tani
A multiple-joint transmission line based on the principle of the periscope was developed to realize the flexible guidance of terahertz (THz) waves. The transmission line has a slightly larger diameter than the standard plastic hollow-pipe waveguide, sufficient stability, low transmission loss, ultrabroadband spectrum, and low dispersion. The transmission line is evaluated using a THz time-domain spectrometer
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Investigation of the Frequency Double-Multiplication Effect in a Sub-THz Gyrotron J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-07 M. Glyavin, I. Zotova, R. Rozental, A. Malkin, A. Sergeev, A. Fokin, V. Rumyantsev, S. Morozov
The effect of frequency multiplication was investigated for a fundamental-harmonic 0.263-THz kW-level gyrotron, in which a certain fraction of its radiation was observed experimentally at the doubled operating frequency. Accurate measurements of the power of such high-frequency generation were carried out based on cyclotron absorption of radiation in a HgTe/CdHgTe quantum-well heterostructure. The
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Polarization Effects of Electro-optic Sampling and Over-rotation for High Field THz Detection J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-04 Gregory Bell; Michael Hilke
With ever increasing availability of terahertz fields, it is important to find suitable detection techniques without compromising the measured dynamic range. Electro-optic terahertz sampling techniques, which are commonly used to detect terahertz fields, exhibit over-rotation at high fields that limit the detection accuracy. Here we discuss a method to correct for over-rotation that put no limits on
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Crystalline Molecular Standards for Low-Frequency Vibrational Spectroscopies J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-03 Sara J. Dampf, Timothy M. Korter
The sub-200 cm−1 (sub-6 THz) vibrations of molecular crystals provide identifying features that are characteristic of each solid sample under study. These distinctive vibrational spectra have driven the development of new techniques and instrumentation in analytical spectroscopy. As terahertz time-domain spectroscopy and low-frequency Raman spectroscopy become increasingly prevalent in non-specialist
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Characterization of the Observed Electric Field and Molecular Relaxation Times for Millimeter-Wave Chirped Pulse Instrumentation. J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-01 G Dhont,D Fontanari,C Bray,G Mouret,A Cuisset,F Hindle,K M Hickson,R Bocquet
In a chirped pulse experiment, the strength of the signal level is proportional to the amplitude of the electric field, which is weaker in the millimeter-wave or submillimeter-wave region than in the microwave region. Experiments in the millimeter region thus require an optimization of the coupling between the source and the molecular system and a method to estimate the amplitude of the electric field
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Gyrotron-Based Technological Systems for Material Processing—Current Status and Prospects J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-07-01 Mikhail Glyavin; Svilen Sabchevski; Toshitaka Idehara; Seitaro Mitsudo
Among various applications of the gyrotrons to the fundamental physical research and to the high-power terahertz science and technologies, the material treatment based on the irradiation by millimeter and sub-millimeter waves is both one of the oldest and most advanced (industrial grade) technologies. In this paper, we present the recent advancements and the current status of both the development of
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Comparison of Terahertz, Microwave, and Laser Power Beaming Under Clear and Adverse Weather Conditions J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-30 Lou Rizzo; John F. Federici; Samuel Gatley; Ian Gatley; James L. Zunino; Kate J. Duncan
Wireless transmission of power from point to point has been developed in two predominate electromagnetic frequency ranges: near-infrared and microwave. In this paper, the prospect of wireless power beaming in the terahertz frequency range is explored with emphasis on the role of adverse weather. Link distance, power transmission, and safety performance of near-infrared, microwave, and terahertz power
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Terahertz Van Atta Retroreflecting Arrays J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-30 Dhruvkumar Desai; Ian Gatley; Christopher Bolton; Lou Rizzo; Samuel Gatley; John F. Federici
As an initial step in developing steerable mirrors for terahertz (THz) wireless communication systems, this paper describes the development of a passive planar terahertz retroreflectors based on the Van Atta array. The retroreflector is optimized and simulated using finite-element modeling (FEM) software, fabricated via a low-cost additive manufacturing method, and characterized using THz time-domain
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Observation of Anomalously Strong Penetration of Terahertz Electric Field Through Terahertz-Opaque Gold Films Into a GaAs/AlGaAs Quantum Well J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-26 S. D. Ganichev; S. N. Danilov; M. Kronseder; D. Schuh; I. Gronwald; D. Bougeard; E. L. Ivchenko; A. Ya. Shul’man
We observe an anomalously high electric field of terahertz (THz) radiation acting on a two-dimensional electron gas (2DEG) placed beneath a thin gold film, which, however, is supposed to be opaque at THz frequencies. We show that the anomalously strong penetration of the THz electric field through a very high conductive gold film emerges if two conditions are fulfilled simultaneously: (i) the film’s
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Frequency-Coded mm-Wave Tags for Self-Localization System Using Dielectric Resonators J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-24 A. Jiménez-Sáez; A. Alhaj-Abbas; M. Schüßler; A. Abuelhaija; M. El-Absi; M. Sakaki; L. Samfaß; N. Benson; M. Hoffmann; R. Jakoby; T. Kaiser; K. Solbach
The paper describes the development of passive, chipless tags for a novel indoor self-localization system operating at high mm-wave frequencies. One tag concept is based on the low-Q fundamental mode of dielectric resonators (DR) which exhibits peak scattering at its resonance frequency. As the radar cross-section (RCS) of DRs at mm-wave frequencies is far too low for the intended application, arrays
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A Constant Corrugation Circular Waveguide for High-Pass Signal Diagnostics in ECEI System at 75–110 GHz J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-24 Hirenkumar V. Dhuda; Piyush N. Patel; Hiteshkumar B. Pandya
In this work, a high-pass waveguide filter with constant circular corrugations is presented. The proposed design allows propagation of HE11 mode which has similar Gaussian characteristics of the signals present in a fusion reactor. The device is designed to operate in W-band, i.e., 75–110 GHz, and it generates a wide passband of approximately 30 GHz. The internal corrugations in the proposed design
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Non-uniformity Correction Algorithm for THz Array Detectors in High-Resolution Imaging Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-19 Rungroj Jintamethasawat; Chayut Thanapirom; Patharakorn Rattanawan; Napat Cota; Natcha Cota; Chia Jia Yi; Kittipong Kasamsook
One of the major challenges in THz imaging using array detectors is the responsivity non-uniformities across different pixels. This is caused by different pixels responding differently and non-linearly to the same incident field. Unfortunately, such responsivity non-uniformities cannot be corrected by the traditional amplitude normalization method, which only accounts for linear responsivity. Therefore
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Terahertz Optical Constants of Solid CO 2 J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-18 Bagvanth Reddy Sangala; Prathap Kumar Jharapla; Rajkumar Golconda; Kurumurthy Guda; G. Vaitheeswaran
We report the optical constants of the solid CO2 (dry ice) measured using terahertz time domain spectroscopy. The CO2 ice sample was grown by vapor deposition method. The optical constants were obtained by minimizing the amplitude of the oscillations of refractive index in the spectral domain. We found that the mean refractive index of CO2 ice at 10 K is 1.485 between 0.2 and 1.6 THz with a standard
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Terahertz Time-of-Flight Tomography Beyond the Axial Resolution Limit: Autoregressive Spectral Estimation Based on the Modified Covariance Method J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-17 Min Zhai; Alexandre Locquet; Cyrielle Roquelet; D. S. Citrin
We present a time-of-flight tomography method for exceeding the naïve axial (i.e., depth) resolution limit of terahertz (THz) deconvolution by autoregressive spectral extrapolation (AR) based on the modified covariance method (AR/MCM). In contrast to Wiener filtering combined with wavelet denoising, AR/MCM does not discard any frequency components in the low signal-to-noise (SNR) regions of the measured
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Highly Localized Defect Mode in Polymer-Based THz Photonic Crystals Fabricated Using Stereolithography J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-16 Serang Park; Yanzeng Li; Micheal McLamb; Brandon Norton; Glenn D. Boreman; Tino Hofmann
A polymer-based one-dimensional photonic crystal with a defect mode was demonstrated for the terahertz frequency range. The photonic crystal was designed to achieve a photonic bandgap centered around 100 GHz with a narrow defect mode at the center frequency. The defect mode allowed a narrow band transmission at the center of photonic bandgap, while the transmitted signal was suppressed in the rest
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A Compact, Low-Power and Constant Output Power 330 GHz Voltage-Controlled Oscillator in 130-nm SiGe BiCMOS J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-15 L. Pantoli; H. Bello; H. J. Ng; D. Kissinger; G. Leuzzi
Nowadays, terahertz and sub-terahertz frequencies are experiencing a significant interest from both academic and industrial world, since they offer a wide and unused spectrum available for different applications, as high-throughput communications, efficient imaging systems and medical uses. In this work an innovative sub-THz voltage-controlled oscillator (VCO) realized with a 130-nm SiGe process is
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Assessing the Performance of Density Functional Theory Methods on the Prediction of Low-Frequency Vibrational Spectra J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-13 Peter A. Banks, Zihui Song, Michael T. Ruggiero
The low-frequency (terahertz) dynamics of condensed phase materials provide valuable insight into numerous bulk phenomena. However, the assignment and interpretation of experimental results require computational methods due to the complex mode types that depend on weak intermolecular forces. Solid-state density functional theory has been used in this regard with great success, yet the selection of
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Clinical Course of High-Frequency Millimeter-Wave (162 GHz) Induced Ocular Injuries and Investigation of Damage Thresholds J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-11 Masami Kojima; Yukihisa Suzuki; Takafumi Tasaki; Yoshinori Tatematsu; Maya Mizuno; Masafumi Fukunari; Hiroshi Sasaki
The objective was to investigate the clinical course of ocular damage and the healing process in eyes exposed to 162 GHz millimeter wave (MMW). As a 162-GHz electromagnetic wave source, a gyrotron FU CW GV was used. An ocular damaged rabbit model with good reproducibility for 162 GHz MMW exposure was developed, and damage occurrence threshold values were obtained. The right eyes of pigmented rabbits
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Toward Mobile Integrated Electronic Systems at THz Frequencies J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-11 Philipp Hillger; Marcel van Delden; Udaya Sampath Miriya Thanthrige; Aya Mostafa Ahmed; Jonathan Wittemeier; Khaled Arzi; Marcel Andree; Benedikt Sievert; Werner Prost; Andreas Rennings; Daniel Erni; Thomas Musch; Nils Weimann; Aydin Sezgin; Nils Pohl; Ullrich R. Pfeiffer
This paper discusses advances related to the integration of future mobile electronic THz systems. Without claiming to provide a comprehensive review of this surging research area, the authors gathered research on selected topics that are expected to be of relevance for the future exploration of components for practical mobile THz imaging and sensing applications. First, a brief technology review of
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A Novel Compact Oversized Rectangular Waveguide Transition Based on Quadruple-Ridged Waveguide for Millimeter Wave Applications J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-10 Jie Deng; Qingyuan Wang
In this paper, a broadband and compact oversized rectangular waveguide transition is proposed. Employing novel quadruple-ridged waveguide technology, two quadruple-ridged waveguides achieve an extreme compactness interconnection from a standard rectangular waveguide to an oversized rectangular waveguide. This design can be used as an alternative way to create a new oversized rectangular waveguide transition
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Broadband Quasi-Optical Dielectric Spectroscopy for Solid and Liquid Samples J. Infrared Millim. Terahertz Waves (IF 1.765) Pub Date : 2020-06-10 Xiaoming Liu; Shuo Yu; Lu Gan; Junsheng Yu
Dielectric materials play a supporting role for electronic circuits. With the development of 5G millimeter wave communication, precision measurement of dielectric property becomes increasingly important. This paper introduces a free-space quasi-optical spectroscopy for complex dielectric property measurement. This spectroscopy can work in both transmission and reflection modes to accommodate both low-loss