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Guo, Hao (author), Zhao, C. (author), Gao, Jianxiang (author), Yang, Wenyun (author), Hu, Xufeng (author), Ma, Xiaobai (author), Jiao, Xuesheng (author), Yang, Jinbo (author), Sun, Kai (author), Chen, Dongfeng (author)To realize concurrently the high-energy density and excellent cycling stability, maximum utilization of redox couple, minimization of detrimental phase transition, and structural degradation of O3-type layered oxide cathodes are critical for developing Na-ion batteries. Ni<sup>2+</sup>/Ni<sup>4+</sup> redox couple showing multielectron...journal article 2023
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Zhang, Chunbo (author), Hu, Mingming (author), van der Meide, Marc (author), Di Maio, F. (author), Yang, Xining (author), Gao, Xiaofeng (author), Li, Kai (author), Zhao, Hailong (author), Li, Chen (author)Meeting the current demand for concrete requires not only mining tons of gravel and sand, but also burning large amounts of fossil fuel resources in cement kilning. Consequently, concrete recycling is crucial to achieving a material-efficient society, especially with the application of various categories of concrete and the goal of phasing...journal article 2023
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Psyllidis, A. (author), Gao, Song (author), Hu, Yingjie (author), Kim, Eun-Kyeong (author), McKenzie, Grant (author), Purves, Ross (author), Yuan, May (author), Andris, Clio (author)In this commentary, we describe the current state of the art of points of interest (POIs) as digital, spatial datasets, both in terms of their quality and affordings, and how they are used across research domains. We argue that good spatial coverage and high-quality POI features — especially POI category and temporality information — are key for...journal article 2022
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Mirzaei, B. (author), Gan, Y. (author), Finkel, M. (author), Groppi, Christopher (author), Young, Abram (author), Walker, Christopher (author), Hu, Qing (author), Gao, J.R. (author)A full demonstration of the Fourier phase grating used as 4.7 THz local oscillator (LO) multiplexer for Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory (GUSTO) is presented in this paper, including its design, modeling, tolerance analysis, and experimental characterizations of the angular and intensity distributions among 2 ×...journal article 2021
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Zhang, Jie (author), Gao, Ling (author), Hu, Jie (author), Wang, Chongjun (author), Hagedoorn, P.L. (author), Li, Ning (author), Zhou, Xing (author)Hypericin is a naturally occurring compound synthesized by certain species of the genus Hypericum, with various pharmacological effects. It is used as a natural photosensitizing agent with great potential in photodynamic therapy. This review discusses the latest results about the biosynthetic pathways and chemical synthetic routes to obtain...journal article 2020
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Gan, Yuner (author), Mirzaei, B. (author), Silva, Jose R.G. (author), Khalatpour, Ali (author), Hu, Qing (author), Groppi, Christopher (author), Siles, Jose V. (author), van der Tak, Floris (author), Gao, J.R. (author)Large heterodyne receiver arrays (~100 pixel) allow astronomical instrumentations to map more area within limited space mission lifetime. One challenge is to generate multiple local oscillator (LO) beams. Here, we succeeded in generating 81 beams at 3.86 THz by combining a reflective, metallic Fourier grating with an unidirectional antenna...journal article 2019
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Mirzaei, B. (author), Silva, J. R.G. (author), Hayton, D (author), Groppi, C (author), Kao, T. Y. (author), Hu, Q. (author), Reno, John L. (author), Gao, J.R. (author)We present an 8-beam local oscillator (LO) for the astronomically significant [OI] line at 4.7 THz. The beams are generated using a quantum cascade laser (QCL) in combination with a Fourier phase grating. The grating is fully characterized using a third order distributed feedback (DFB) QCL with a single mode emission at 4.7 THz as the input....journal article 2017
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Van Marrewijk, N. (author), Mirzaei, B. (author), Hayton, D. (author), Gao, J.R. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author)We have performed frequency locking of a dual, forward reverse emitting third-order distributed feedback quantum cascade laser (QCL) at 3.5 THz. By using both directions of THz emission in combination with two gas cells and two power detectors, we can for the first time perform frequency stabilization, while monitor the frequency locking quality...journal article 2015
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Hayton, D.J. (author), Khudchenko, A. (author), Pavelyev, D.G. (author), Hovenier, J.N. (author), Baryshev, A. (author), Gao, J.R. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author), Vaks, V. (author)We report on the phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser (QCL) using a room temperature GaAs/AlAs superlattice diode as both a frequency multiplier and an internal harmonic mixer. A signal-to-noise level of 60?dB is observed in the intermediate frequency signal between the 18th harmonic of a 190.7?GHz...journal article 2013
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Cui, M. (author), Hovenier, J.N. (author), Ren, Y. (author), Vercruyssen, N. (author), Gao, J.R. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author)We report on both measurements and simulations of the beam profile and wavefront of a single-mode, 3.5?THz quantum cascade wire laser, incorporating a lateral corrugated metal-metal waveguide, 3rd-order distributed feedback grating. The intrinsic wavefront was measured by using a Hartmann wavefront sensor (HWS) without any optical components...journal article 2013
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Kloosterman, J.L. (author), Hayton, D.J. (author), Ren, Y. (author), Kao, T.Y. (author), Hovenier, J.N. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Hu, Q. (author), Walker, C.K. (author), Reno, J.L. (author)We report on a heterodyne receiver designed to observe the astrophysically important neutral atomic oxygen [OI] line at 4.7448?THz. The local oscillator is a third-order distributed feedback quantum cascade laser operating in continuous wave mode at 4.741?THz. A quasi-optical, superconducting NbN hot electron bolometer is used as the mixer. We...journal article 2013
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Ren, Y. (author), Hayton, D.J. (author), Hovenier, J.N. (author), Cui, M. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Shi, S.C. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author)We demonstrate an experimental scheme to simultaneously stabilize the frequency and amplitude of a 3.5 THz third-order distributed feedback quantum cascade laser as a local oscillator. The frequency stabilization has been realized using a methanol absorption line, a power detector, and a proportional-integral-derivative (PID) loop. The amplitude...journal article 2012
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Ren, Y. (author), Hovenier, J.N. (author), Cui, M. (author), Hayton, D.J. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Shi, S.C. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author)We report frequency locking of two 3.5-THz third-order distributed feedback (DFB) quantum cascade lasers (QCLs) by using methanol molecular absorption lines, a proportional-integral-derivative controller, and a NbN bolometer. We show that the free-running linewidths of the QCLs are dependent on the electrical and temperature tuning coefficients....journal article 2012
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Ren, Y. (author), Hovenier, J.N. (author), Higgins, R. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Shi, S.C. (author), Klein, B. (author), Kao, T.Y. (author), Hu, Q. (author), Reno, J.L. (author)A frequency tunable terahertz heterodyne spectrometer, based on a third-order distributed feedback quantum cascade laser as a local oscillator, has been demonstrated by measuring molecular spectral lines of methanol (CH3OH) gas at 3.5 THz. By varying the bias voltage of the laser, we achieved a tuning range of ? 1?GHz of the lasing frequency,...journal article 2011
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Ren, Y. (author), Hovenier, J.N. (author), Higgins, R. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Shi, S.C. (author), Bell, A. (author), Klein, B. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author)A terahertz (THz) heterodyne spectrometer is demonstrated based on a quantum cascade laser (QCL) as a local oscillator (LO) and an NbN hot electron bolometer as a mixer, and it is used to measure high-resolution molecular spectral lines of methanol (CH3OH) between 2.913–2.918 THz. The spectral lines are taken from a gas cell containing methanol...journal article 2010
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Khosropanah, P. (author), Baryshev, A. (author), Zhang, W. (author), Jellema, W. (author), Hovenier, J.N. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Paveliev, D.G. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author), Klein, B. (author), Hesler, J.L. (author)We demonstrate the phase locking of a 2.7 THz metal–metal waveguide quantum cascade laser (QCL) to an external microwave signal. The reference is the 15th harmonic, generated by a semiconductor superlattice nonlinear device, of a signal at 182 GHz, which itself is generated by a multiplier chain (x12) from a microwave synthesizer at ~15 GHz....journal article 2009
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Baryshev, A. (author), Hovenier, J.N. (author), Adam, A.J.L. (author), Kaalynas, I. (author), Gao, J.R. (author), Klaassen, T.O. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author)We have studied the phase locking and spectral linewidth of an ? 2.7?THz quantum cascade laser by mixing its two lateral lasing modes. The beat signal at about 8?GHz is compared with a microwave reference by applying conventional phase lock loop circuitry with feedback to the laser bias current. Phase locking has been demonstrated, resulting in...journal article 2006
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Adam, A.J.L. (author), Kaalynas, I. (author), Hovenier, J.N. (author), Klaassen, T.O. (author), Gao, J.R. (author), Orlova, E.E. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author)The need to reach single-mode lasing and minimize at the same time the electrical dissipation of cryogenically operated terahertz quantum cascade lasers may result in small and subwavelength cavity dimensions. To assess the influence of such dimensions on the shape of the laser emission, we have measured the beam pattern of two metal-metal...journal article 2006
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- Orlova, E.E. (author), Hovenier, J.N. (author), Klaassen, T.O. (author), Kasalynas, I. (author), Adam, A.J.L. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author) journal article 2006
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Gao, J.R. (author), Hovenier, J.N. (author), Yang, Z.Q. (author), Baselmans, J.J.A. (author), Baryshev, A. (author), Hajenius, M. (author), Klapwijk, T.M. (author), Adam, A.J.L. (author), Klaassen, T.O. (author), Williams, B.S. (author), Kumar, S. (author), Hu, Q. (author), Reno, J.L. (author)We report the first demonstration of an all solid-state heterodyne receiver that can be used for high-resolution spectroscopy above 2?THz suitable for space-based observatories. The receiver uses a NbN superconducting hot-electron bolometer as mixer and a quantum cascade laser operating at 2.8?THz as local oscillator. We measure a double...journal article 2005