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- Tao, Y. (author), Gao, D.W. (author), Wang, H.Y. (author), Zhang, X. (author), Ghasimi, S.M.D. (author), Ozgun, H. (author), Ersahin, M.E. (author), Zhou, Z.B. (author), Liu, G. (author), Temudo, M.F. (author), Kloek, J. (author), Spanjers, H. (author), De Kreuk, M.K. (author), Van Lier, J.B. (author) conference paper 2014
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Ren, Y. (author), Gao, J.R. (author), Hovenier, J.N.Higgins, R. (author), Zhang, W. (author), Bell, A. (author), Klein, B. (author), Klapwijk, T.M. (author)High-resolution heterodyne spectrometers operating at above 2 THz are crucial for detecting, e.g., the HD line at 2.7 THz and oxygen OI line at 4.7 THz in astronomy. The potential receiver technology is a combination of a hot electron bolometer (HEB) mixer and a THz quantum cascade laser (QCL) local oscillator (LO).Here we report the first...conference paper 2010
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Gao, L. (author), Zhang, L.M. (author), Chen, H.X. (author)Due to hilly terrain and frequent heavy rainstorms, debris flow is one of the most common and catastrophic hazards in Hong Kong. To mitigate the debris flow risk, prediction of the magnitude and consequence of debris flow is essential. The objective of this paper is to simulate debris flow hazards in a study area in Hong Kong. Assessment of the...conference paper 2015
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Zhang, W. (author), Gao, J.R. (author), Khosropanah, P. (author), Bansal, T. (author), Klapwijk, T.M. (author), Miao, W. (author), Shi, S.C. (author)We report the sensitivity of a superconducting NbN hot electron bolometer mixer integrated with a tight spiral antenna at 5.3 THz. Using a measurement setup with black body calibration sources and a beam splitter in vacuo, and an antireflection coated Si lens, we obtained a double sideband receiver noise temperature of 1150 K, which is 4.5 times...conference paper 2010
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Li, Meng (author), Gao, Jianbo (author), Zhang, Zijian (author), Fu, Chaoping (author), Lal, C. (author), Conti, M. (author)Shortest distance queries over large-scale graphs bring great benefits to various applications, i.e., save planning time and travelling expenses. To protect the sensitive nodes and edges in the graph, a user outsources an encrypted graph to an untrusted server without losing the query ability. However, no prior work has considered the user...conference paper 2022
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Li, Shizhen (author), Liu, X. (author), Jiang, Jing (author), Tan, C. (author), Gao, Chenshan (author), Liu, Yang (author), Ye, H. (author), Zhang, Kouchi (author)Cu-Ag core-shell (CS) nanoparticle (NP) is considered as a cost-effective alternative material to nano silver sintering material in die attachment application. To further reduce the cost, the thickness of the Ag shell can be adjusted. Whereas the shell thickness will also affect the thermal stability of the Cu-Ag CSNPs. In this study, molecular...conference paper 2022
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Gao, Y. (author), Dong, J. (author), Isabella, O. (author), Zeman, M. (author), Zhang, G (author)Diverse solar irradiance spectra can be observed under different conditions of time, date, location, weather, etc. Since the solar irradiance spectrum is required by certain scientific and engineering applications, obtaining accurate spectral data is essential. Measurements by spectrophotometers are able to achieve accurate real-time data with...conference paper 2016
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Gao, Hanyan (author), Zhang, Jing (author), Zhu, Yingcan (author), Guo, Ruiqian (author), Zhang, Wanlu (author), Zhang, Kouchi (author), Liu, Pan (author)With the trend of miniaturization and the increasing power density, the operating temperature of electronic devices keeps climbing, especially for wide band-gap semiconductors such as silicon carbide and gallium nitride. The high operating temperature up to 250℃ brings challenges to encapsulation materials since traditional encapsulation...conference paper 2022
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Li, Meng (author), Zhang, Mingwei (author), Gao, Jianbo (author), Lal, C. (author), Conti, M. (author), Alazab, Mamoun (author)Location-Based Services (LBSs) depend on a Service Provider (SP) to store data owners’ geospatial data and to process data users’ queries. For example, a Yelp user queries the SP to retrieve the k nearest Starbucks by submitting her/his current location. It is well-acknowledged that location privacy is vital to users and several prominent...conference paper 2022
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Li, Shizhen (author), Liu, X. (author), Gao, Chenshan (author), Wang, S. (author), Li, Jun (author), Ye, Huaiyu (author), Zhang, Kouchi (author), Wu, Shaohui (author)The significance of wafer bonding is fundamental to the progression of electronic systems. Common fabrication techniques for Cu pillars play a crucial role in establishing resilient and efficient interconnects within semiconductor devices. It is imperative to explore the potential of nano-copper as an alternative material to overcome limitations...conference paper 2024
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Hayton, D.J. (author), Gao, J.R. (author), Kooi, J.W. (author), Ren, Y. (author), Zhang, W. (author), De Lange, G. (author)We report on a method to stabilize a hot electron bolometer (HEB) mixer at 2.5 THz. The technique utilizes feedback control of the local oscillator (LO) laser power by means of a swing-arm actuator placed in the optical beam path. We demonstrate that this technique yields a factor of 50 improvement in the spectroscopic Allan variance time which...journal article 2012
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Zhang, W. (author), Khosropanah, P. (author), Gao, J.R. (author), Kollberg, E.L. (author), Yngvesson, K.S. (author), Bansal, T. (author), Barends, R. (author), Klapwijk, T.M. (author)We have measured the noise temperature of a single, sensitive superconducting NbN hot electron bolometer (HEB) mixer in a frequency range from 1.6 to 5.3 THz, using a setup with all the key components in vacuum. By analyzing the measured receiver noise temperature using a quantum noise (QN) model for HEB mixers, we confirm the effect of QN. The...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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Zhang, W. (author), Khosropanah, P. (author), Gao, J.R. (author), Bansal, T. (author), Klapwijk, T.M. (author), Miao, W. (author), Shi, S.C. (author)We report the measured sensitivities of a superconducting NbN hot electron bolometer (HEB) heterodyne receiver at 5.25 THz. Terahertz (THz) radiation is quasioptically coupled to a HEB mixer with a lens and a spiral antenna. Using a measurement setup with black body calibration sources and a beam splitter in vacuo, and an antireflection coated...journal article 2010
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Khosropanah, P. (author), Zhang, W. (author), Hovenier, J.N. (author), Gao, J.R. (author), Klapwijk, T.M. (author), Amanti, M.I. (author), Scalari, G. (author), Faist, J. (author)We report a heterodyne receiver using a superconducting NbN hot electron bolometer (HEB) integrated with a tight winding spiral antenna as mixer and a distributed feedback (DFB) terahertz quantum cascade laser (QCL) operating at 3.42 THz as local oscillator. The aim is to demonstrate the readiness of both devices for the detection of OH lines at...journal article 2008
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Tan, C. (author), Gao, Chenshan (author), Zhou, Quan (author), van Driel, W.D. (author), Ye, H. (author), Zhang, Kouchi (author)The authors regret that one of the affiliations (affiliation f) was incorrectly omitted in the original manuscript. The corrected list of affiliations is as shown below. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.journal article 2021
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The inactivation mechanism of chemical disinfection against SARS-CoV-2: From MD and DFT perspectivesTan, C. (author), Gao, Chenshan (author), Zhou, Quan (author), van Driel, W.D. (author), Ye, H. (author), Zhang, Kouchi (author)Exploring effective disinfection methods and understanding their mechanisms on the new coronavirus is becoming more active due to the outbreak of novel coronavirus pneumonia (COVID-19) caused by severe acute respiratory coronavirus 2 (SARS-CoV-2). By combining molecular dynamics and first-principles calculations, we investigate the...journal article 2020
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Liu, X. (author), Li, Shizhen (author), Tan, C. (author), Gao, Chenshan (author), Liu, Yang (author), Ye, H. (author), Zhang, Kouchi (author)Nano copper sintering technology has great potential to be widely applied in the wide-bandgap semiconductor packaging. In order to investigate the coalescence kinetics of copper nano particles for this application, a molecular dynamic (MD) simulation was carried out at low temperature on a special model containing two substrate and multiple...journal article 2022
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Tang, H. (author), Gao, Chenshan (author), Yang, Huiru (author), Sacco, L.N. (author), Sokolovskij, R. (author), Ye, H. (author), Vollebregt, S. (author), Fan, X. (author), Zhang, Kouchi (author)In this paper, tin oxidation (SnO x )/tin-sulfide (SnS) heterostructures are synthesized by the post-oxidation of liquid-phase exfoliated SnS nanosheets in air. We comparatively analyzed the NO2 gas response of samples with different oxidation levels to study the gas sensing mechanisms. The results show that the samples oxidized at 325 °C are...journal article 2021
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Gao, Y. (author), Zhang, Yuqing (author), Zhang, Chao (author), Liu, X. (author), Jing, R. (author)Bitumen in asphalt pavements reacts slowly with atmospheric oxygen, resulting in oxidative ageing. This oxidative reaction is strongly dependent on the physical diffusion of the oxygen into the bitumen. This study aims to use molecular dynamics (MD) simulation to investigate the oxygen diffusion into the bitumen film and analyse the effects...journal article 2022