Searched for: subject%3A%22terahertz%22
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Gaspar Silva, Jose Rui (author), Finkel, M. (author), Laauwen, Wouter M. (author), Yates, S.J.C. (author), Mirzaei, B. (author), Vercruyssen, N. (author), Young, Abram (author), Walker, Christopher (author), Gao, J.R. (author)
We have simulated and measured the beam properties of lens-antenna coupled hot electron bolometer mixers at a few supra-terahertz frequencies between 1.4 and 5.3 THz. The quasi-optical structures consist of an elliptical lens and a logarithmic spiral antenna. The model used for our simulations consists of a finite-element analysis to simulate...
journal article 2023
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Leitenstorfer, Alfred (author), Moskalenko, Andrey S. (author), Kampfrath, Tobias (author), Kono, Junichiro (author), Kim, Ki Yong (author), Zhang, Xi Cheng (author), Walker, Christopher (author), Gao, J.R. (author), Li, Chong (author)
Terahertz (THz) radiation encompasses a wide spectral range within the electromagnetic spectrum that extends from microwaves to the far infrared (100 GHz-∼30 THz). Within its frequency boundaries exist a broad variety of scientific disciplines that have presented, and continue to present, technical challenges to researchers. During the past...
review 2023
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Zhang, Heng (author), Debroye, Elke (author), Fu, Shuai (author), González, Miriam C.Rodriguez (author), du Fossé, I. (author), Geuchies, Jaco J. (author), Gao, Lei (author), Yu, Xiaoqing (author), Houtepen, A.J. (author)
Synergically combining their respective ultrahigh charge mobility and strong light absorption, graphene (Gr)/semiconductor heterostructures are promising building blocks for efficient optoelectronics, particularly photodetectors. Charge transfer (CT) across the heterostructure interface crucially determines device efficiency and functionality...
journal article 2023
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Fiorellini Bernardis, A. (author), Sberna, P.M. (author), Bueno Lopez, J. (author), Zhang, H. (author), Llombart, Nuria (author), Neto, A. (author)
Drude's description of the response of low-temperature gallium arsenide to optical pulse excitation is used to evaluate the components of a time-domain Norton equivalent circuit of a photoconductive antenna (PCA) source. The saturation of the terahertz (THz) radiated power occurring at large optical excitation levels was previously associated...
journal article 2023
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Hoogelander, M. (author), Alonso Del Pino, M. (author), Llombart, Nuria (author), Spirito, M. (author)
The continuous advancements in the coverage and sensitivity of terahertz direct-detector imagers places increasing constraints on the test benches needed for characterization. Already, relative differences on the order of a few decibels are observed between simulated and measured performance in the state-of-the-art literature. This...
conference paper 2023
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Alonso Del Pino, M. (author), Bosma, S. (author), Jung-Kubiak, C. (author), Bueno, J. (author), Chattopadhyay, G. (author), Llombart, Nuria (author)
In this paper, we present a quasi-optical power distribution architecture based on the use of an integrated lens antenna that generates a uniform aperture field distribution. By using such distribution in combination with an integrated lens array, an efficient and scalable quasi-optical power distribution can be achieved at THz frequencies....
conference paper 2023
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van Berkel, S.L. (author), Alonso Del Pino, M. (author), Jung-Kubiak, Cecile (author), Chattopadhyay, Goutam (author)
The development of a low focal number and low-mass lens antenna is presented that enables terahertz spectroscopy applications on ultracompact platforms. The antenna operates efficiently over a 20% fractional bandwidth, from 450 to 550 GHz, with a gain of 50 dBi at 500 GHz. The antenna consists of a hyperbolic silicon lens that is placed in a...
journal article 2023
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Marting, Louis (author)
Terahertz astronomy has been exceptionally unexplored until the last decades due to a technological gap, but exactly at these wavelengths the most distant galaxies appear very bright. Efficient instruments that are capable of spectrometry are essential in understanding the physics of these distant objects. Within the framework of this thesis, an...
master thesis 2022
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Neves Almeida Lopes, Tamira (author)
When looking up to the sky and trying to detect the photons of far away stars that are still in formation, we can get access to knowledge we never had before. In order to do this, we must make sure we truly understand the nature of how photons behave in accordance to each other and to our detectors.In quantum optics we can see that these photons...
bachelor thesis 2022
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Ligthart, Liam (author)
More insight has been gathered on the performance of the SPLITTER (Stationary spectrum Plus Low-rank Iterative TransmiTtance EstimatoR) algorithm as developed by Brackenhoff for denoising data gathered from observations of high-redshift galaxies. By using matrix decomposition to split the gathered data into a low-rank atmosphere matrix and a...
bachelor thesis 2022
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Fiorellini Bernardis, A. (author)
In recent years, the interest in terahertz technology witnessed a constant increasing interest and attention from the scientific community, as it allows to unlock the THz bandwidth, that can be used for a wide range of applications: it helps the study of biological samples and help medical diagnostics; it serves as a harmless non-destructive...
doctoral thesis 2022
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Gasparsilva, Jose Rui (author), Finkel, M. (author), Laauwen, Wouter (author), Westerweld, Menno (author), More, Nikhil (author), Young, Abram (author), Kulesa, Craig (author), Walker, Christopher (author), Van der Tak, Floris (author), Gao, J. (author)
We report a high accuracy pointing technique for quasi-optical hot electron bolometer (HEB) mixers in focal-plane arrays designed to operate at 1.4, 1.9, and 4.7 THz. The high accuracy pointing is achieved by prealignment of a HEB chip to a lens, measuring the angular error of each mixer in an array assembly, and then realignment of the chip...
journal article 2022
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Myers, N.J. (author), Heath, Robert W. (author)
Phased arrays, commonly used in IEEE 802.11ad and 5G radios, are capable of focusing radio frequency signals in a specific direction or a spatial region. Beamforming achieves such directional or spatial concentration of signals and enables phased array-based radios to achieve high data rates. Designing beams for millimeter wave and terahertz...
journal article 2022
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Walker, C (author), Kusela, C. (author), Young, A (author), Verts, W. (author), Gao, J.R. (author), Hu, Qing (author), Silva, J. R.G. (author), Mirzaei, B. (author), Laauwen, Wouter (author)
Gal/Xgal U/LDB Spectroscopic/ Stratospheric THz Observatory (GUSTO) is a NASA Explorers Mission of Opportunity that will make large scale maps of the Milky Way and Large Magellanic Cloud in three important interstellar lines: [CII], [OI], and [NII] at 158, 63, and 205 μm, respectively. During its ~75 day stratospheric (~36 km) flight, GUSTO’s 0...
conference paper 2022
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Tan, C. (author), Wang, S. (author), Li, Shizhen (author), Liu, X. (author), Wei, Jia (author), Zhang, Kouchi (author), Ye, H. (author)
Owing to the outstanding physical properties of graphene, its biosensing applications implemented by the terahertz metasurface are widely concerned and studied. Here, we present a novel design of the graphene metasurface, which consists of an individual graphene ring and an H-shaped graphene structure. The graphene metasurface exhibits a dual...
journal article 2022
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Tan, C. (author), Wang, S. (author), Yang, Huiru (author), Huang, Qianming (author), Li, Shizhen (author), Liu, X. (author), Ye, H. (author), Zhang, Kouchi (author)
Recent reports focus on the hydrogenation engineering of monolayer boron phosphide and simultaneously explore its promising applications in nanoelectronics. Coupling density functional theory and finite element method, we investigate the bowtie triangle ring microstructure composed of boron phosphide with hydrogenation based on structural and...
journal article 2022
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Hempel, Hannes (author), Savenije, T.J. (author), Stolterfoht, Martin (author), Neu, Jens (author), Failla, M. (author), Paingad, Vaisakh C. (author), Kužel, Petr (author), Zhao, J. (author), Siebbeles, L.D.A. (author)
Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Here, the expertise from fifteen laboratories is combined to quantitatively model the current-voltage characteristics of a solar cell from such measurements....
journal article 2022
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Gan, Y. (author), Mirzaei, B. (author), Silva, J. R.G. (author), Laauwen, W. (author), Van Der Tak, F. F.S. (author), Gao, J.R. (author)
We present an analysis of the bandwidth of an asymmetric 8-beam Fourier grating as the beam multiplexer for a 4.7 THz local oscillator used in a heterodyne receiver. We take the grating designed for NASA GUSTO balloon observatory as an example to address the bandwidth question although it does not need to operate over a wide frequency range....
journal article 2022
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Lasisi, S.O. (author), Benson, T.M. (author), Greenaway, M.T. (author), Gradoni, G. (author), Cools, K. (author)
We demonstrate how the coupling of a full-wave time-domain boundary element method (BEM) solver with a circuit solver can be used to model 1) the generation of high frequency oscillations in resonant tunneling diode (RTD) oscillators, and 2) the mutual coupling and synchronization of non-identical RTDs with significant differences in frequencies...
journal article 2022
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Pascual Laguna, A. (author), Karatsu, K. (author), Thoen, David (author), Murugesan, Vignesh (author), Buijtendorp, B.T. (author), Endo, A. (author), Baselmans, J.J.A. (author)
A superconducting microstrip half-wavelength resonator is proposed as a suitable band-pass filter for broadband moderate spectral resolution spectroscopy for terahertz (THz) astronomy. The proposed filter geometry has a free spectral range of an octave of bandwidth without introducing spurious resonances, reaches a high coupling efficiency in...
journal article 2021
Searched for: subject%3A%22terahertz%22
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