Through-substrate terahertz time-domain reflection spectroscopy for environmental graphene conductivity mapping
Open accessAbstract
We demonstrate how terahertz time-domain spectroscopy (THz-TDS) operating in reflection geometry can be used for quantitative conductivity mapping of large area chemical vapor deposited graphene films through silicon support. We validate the technique against measurements performed using the established transmission based THz-TDS. Our through-substrate approach allows unhindered access to the graphene top surface and thus, as we discuss, opens up pathways to perform in situ and in-operando THz-TDS using environmental cells.
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Existing experimental techniques to circumvent phase sensitivity in reflection geometry are often material-specific and cannot be universally applied to all sample types.
“Despite their effectiveness, these techniques often tend to be material-specific and cannot be universally applied to all sample types.”
From Robust phase correction techniques for terahertz time-domain reflection spectroscopy (2024) · cites this paper as [25]
Cites
Large-Area Synthesis of High-Quality and Uniform Graphene Films on Copper Foils
Li, X., Cai, W., An, J., Kim, S., Nah, J., Yang, D., Piner, R. D., Velamakanni, A., Jung, I., Tutuc, E., et al. (2009) · Science · doi:10.1126/science.1171245 · Cited by 11,245 · see citing works
Roll-to-roll production of 30-inch graphene films for transparent electrodes
Bae, S., Kim, H., Lee, Y., Xu, X., Park, J.-S., Zheng, Y., Balakrishnan, J., Lei, T., Kim, H. R., Song, Y. I., et al. (2010) · Nature Nanotechnology · doi:10.1038/nnano.2010.132 · Cited by 8,158 · cited 6× · see citing works
“This small 2%–5% conductivity increase is at the same order of magnitude but slightly higher than what was reported in an earlier work using direct electrical measurements on a 44 80lm2 patch of CVD graphene on SiO2/Si wafer support.”
BackgroundInfluentialDetection of individual gas molecules adsorbed on graphene
Schedin, F., Geim, A. K., Morozov, S. V., Hill, E. W., Blake, P., Katsnelson, M. I., & Novoselov, K. S. (2007) · Nature Materials · doi:10.1038/nmat1967 · Cited by 8,028 · cited 1× · see citing works
“8 THz-TDS of graphene films inside environmental cells as graphene’s electrical conductivity is being modified by the local environment [31, 32].”
BackgroundScience and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems
Ferrari, A. C., Bonaccorso, F., Fal’ko, V. I., Novoselov, K. S., Roche, S., Bøggild, P., Borini, S., Koppens, F. H. L., Palermo, V., Pugno, N. M., et al. (2014) · Nanoscale · doi:10.1039/c4nr01600a · Cited by 3,011 · cited 1× · see citing works
“For scaled graphene manufacturing and many emerging device applications, often not growth itself but adequate characterisation and quality control of the graphene films has become the key challenge [6, 7] .”
BackgroundFar-infrared time-domain spectroscopy with terahertz beams of dielectrics and semiconductors
Grischkowsky, D., Keiding, S., van Exter, M., & Fattinger, C. (1990) · Journal of the Optical Society of America B · doi:10.1364/josab.7.002006 · Cited by 2,239 · see citing works
Broadband graphene terahertz modulators enabled by intraband transitions
Sensale‐Rodriguez, B., Yan, R., Kelly, M. M., Fang, T., Tahy, K., Hwang, W. S., Jena, D., Liu, L., & Xing, H. G. (2012) · Nature Communications · doi:10.1038/ncomms1787 · Cited by 1,092 · cited 1× · see citing works
“Among a range of emerging contactless electrical characterisation methods [6], terahertz time-domain spectroscopy (THz-TDS) operating in transmission geometry has demonstrated to accurately map the conductivity and mobility of graphene over large areas, producing data consistent with the Drude model to describe graphe…”
BackgroundSynthesis challenges for graphene industry
Lin, L., Peng, H.-L., & Liu, Z.-F. (2019) · Nature Materials · doi:10.1038/s41563-019-0341-4 · Cited by 448 · see citing works
Gas sensing using terahertz time-domain spectroscopy
Mittleman, D. M., Jacobsen, R. H., Neelamani, R., Baraniuk, R. G., & Nuss, M. C. (1998) · Applied Physics B: Lasers and Optics · doi:10.1007/s003400050520 · Cited by 379 · see citing works
THz reflection spectroscopy of liquid water
Thrane, L., Jacobsen, R. H., Uhd Jepsen, P., & Keiding, S. R. (1995) · Chemical Physics Letters · doi:10.1016/0009-2614(95)00543-d · Cited by 339 · cited 1× · see citing works
“substrate) and second (substrate-graphene-air) reflections as reference and sample signals, respectively [22].”
BackgroundSynthesis of Graphene Films on Copper Foils by Chemical Vapor Deposition
Li, X.-S., Colombo, L., & Ruoff, R. S. (2016) · Advances in Materials · doi:10.1002/adma.201504760 · Cited by 335 · see citing works
Resistive graphene humidity sensors with rapid and direct electrical readout
Smith, A., Elgammal, K., Niklaus, F., Delin, A., Fischer, A., Vaziri, S., Forsberg, F., Råsander, M., Hugosson, H., Bergqvist, L., et al. (2015) · Nanoscale · doi:10.1039/c5nr06038a · Cited by 266 · cited 2×
“The fact that the conductivity change is close to previous work [30] is promising and suggests a method of performing in-situ and in-operando”
Graphene conductance uniformity mapping.
Buron, J. D., Petersen, D. H., Bøggild, P., Cooke, D., Hilke, M., Sun, J., Whiteway, E., Nielsen, P., Hansen, O., Yurgens, A., et al. (2012) · Nano letters (Print) · doi:10.1021/nl301551a · Cited by 183 · cited 4× · see citing works
“Such approximations were also used for analysing transmission measurements [8, 24], which have been validated using micro four-point probe measurements [8].”
BackgroundMethodInfluentialEnergy Gap Interpretation of Experiments on Infrared Transmission through Superconducting Films
Tinkham, M. (1956) · Physical Review · doi:10.1103/physrev.104.845 · Cited by 177 · see citing works
Braeuninger-Weimer, P., Brennan, B., Pollard, A., & Hofmann, S. (2016) · Chemistry of Materials · doi:10.1021/acs.chemmater.6b03241 · Cited by 144 · cited 8× · see citing works
“This small 2%–5% conductivity increase is at the same order of magnitude but slightly higher than what was reported in an earlier work using direct electrical measurements on a 44 80lm2 patch of CVD graphene on SiO2/Si wafer support.”
BackgroundMethodInfluentialSelf-citationMapping the electrical properties of large-area graphene
Bøggild, P., Mackenzie, D. M. A., Whelan, P. R., Petersen, D. H., Buron, J. D., Zurutuza, A., Gallop, J., Hao, L., & Jepsen, P. (2017) · 2D Materials · doi:10.1088/2053-1583/aa8683 · Cited by 131 · see citing works
CVD-Enabled Graphene Manufacture and Technology
Hofmann, S., Braeuninger‐Weimer, P., & Weatherup, R. S. (2015) · The Journal of Physical Chemistry Letters · doi:10.1021/acs.jpclett.5b01052 · Cited by 120 · cited 6× · see citing works
“This small 2%–5% conductivity increase is at the same order of magnitude but slightly higher than what was reported in an earlier work using direct electrical measurements on a 44 80lm2 patch of CVD graphene on SiO2/Si wafer support.”
BackgroundInfluentialSelf-citationTerahertz imaging and spectroscopy of large-area single-layer graphene.
Tomaino, J., Jameson, A., Kevek, J. W., Paul, M., van der Zande, A. M., Barton, R. A., McEuen, P., Minot, E., & Lee, Y.-S. (2011) · Optics Express · doi:10.1364/oe.19.000141 · Cited by 110 · see citing works
Buron, J. D., Pizzocchero, F., Jepsen, P., Petersen, D. H., Caridad, J., Jessen, B. S., Booth, T., & Bøggild, P. (2015) · Scientific Reports · doi:10.1038/srep12305 · Cited by 105 · cited 1× · see citing works
“Drift and field-effect mobilities can then be extracted by fitting the conductivity spectra to Drude model [14], and measuring conductivity changes in response to back-gate voltages [15], respectively.”
MethodWiley Series in Pure and Applied Optics
Assanto, G. (2012) · doi:10.1002/9781118414637.scard · Cited by 93 · cited 1×
“The frequency dependent THz beam diameter can be estimated from the focal length of the off-axis mirror and the collimated beam size using Gaussian optics [26], but this estimate is only reliable if the Rayleigh range of the focusing mirror is greater than substrate thickness [27, 28].”
BackgroundTerahertz Properties of Graphene
Docherty, C. J., & Johnston, M. (2012) · Journal of Infrared Millimeter and Terahertz Waves · doi:10.1007/s10762-012-9913-y · Cited by 90 · cited 1× · see citing works
“Among a range of emerging contactless electrical characterisation methods [6], terahertz time-domain spectroscopy (THz-TDS) operating in transmission geometry has demonstrated to accurately map the conductivity and mobility of graphene over large areas, producing data consistent with the Drude model to describe graphe…”
BackgroundBuron, J. D., Pizzocchero, F., Jessen, B. S., Booth, T., Nielsen, P., Hansen, O., Hilke, M., Whiteway, E., Jepsen, P., Bøggild, P., et al. (2014) · Nano letters (Print) · doi:10.1021/nl5028167 · Cited by 82 · cited 1× · see citing works
“Among a range of emerging contactless electrical characterisation methods [6], terahertz time-domain spectroscopy (THz-TDS) operating in transmission geometry has demonstrated to accurately map the conductivity and mobility of graphene over large areas, producing data consistent with the Drude model to describe graphe…”
BackgroundAtmospheric doping effects in epitaxial graphene: correlation of local and global electrical studies
Panchal, V., Giusca, C., Lartsev, A., Martin, N. A., Cassidy, N., Myers-Ward, R., Gaskill, D., & Kazakova, O. (2016) · doi:10.1088/2053-1583/3/1/015006 · Cited by 56 · cited 2×
“in unintentional doping from other moieties in the ambient air [31].”
BackgroundTerahertz wafer-scale mobility mapping of graphene on insulating substrates without a gate.
Buron, J. D., Mackenzie, D. M. A., Petersen, D. H., Pesquera, A., Centeno, A., Bøggild, P., Zurutuza, A., & Jepsen, P. (2015) · Optics Express · doi:10.1364/oe.23.030721 · Cited by 54 · cited 1× · see citing works
“Drift and field-effect mobilities can then be extracted by fitting the conductivity spectra to Drude model [14], and measuring conductivity changes in response to back-gate voltages [15], respectively.”
MethodLin, H., Braeuninger‐Weimer, P., Kamboj, V. S., Jessop, D. S., Degl’Innocenti, R., Beere, H. E., Ritchie, D. A., Zeitler, J. A., & Hofmann, S. (2017) · Scientific Reports · doi:10.1038/s41598-017-09809-7 · Cited by 49 · cited 4× · see citing works
“The demonstration of the through-substrate reflection measurement means that conductivity can be reasonably estimated directly from the first transmitted or reflected pulse, as previously demonstrated [13, 16], even if the pulse has already undergone a longer propagation path and through the supporting substrate on a…”
BackgroundMethodInfluentialSelf-citationWhelan, P. R., Iwaszczuk, K., Wang, R., Hofmann, S., Bøggild, P., & Jepsen, P. U. (2017) · Optics Express · doi:10.1364/oe.25.002725 · Cited by 43 · see citing works
Self-citationMackenzie, D. M. A., Whelan, P. R., Bøggild, P., Jepsen, P., Redo-Sanchez, A., Etayo, D., Fabricius, N., & Petersen, D. H. (2018) · Optics Express · doi:10.1364/oe.26.009220 · Cited by 42 · see citing works
Perspective on terahertz spectroscopy of graphene
Ivanov, I., Bonn, M., Mics, Z., & Turchinovich, D. (2015) · Europhysics Letters (EPL) · doi:10.1209/0295-5075/111/67001 · Cited by 37 · cited 1× · see citing works
“Among a range of emerging contactless electrical characterisation methods [6], terahertz time-domain spectroscopy (THz-TDS) operating in transmission geometry has demonstrated to accurately map the conductivity and mobility of graphene over large areas, producing data consistent with the Drude model to describe graphe…”
BackgroundBraeuninger-Weimer, P., Funke, S., Wang, R.-Z., Thiesen, P., Tasche, D., Viöl, W., & Hofmann, S. (2018) · ACS Nano · doi:10.1021/acsnano.8b04167 · Cited by 36 · see citing works
Self-citationThe Role and Control of Residual Bulk Oxygen in the Catalytic Growth of 2D Materials
Burton, O., Babenko, V., Veigang-Radulescu, V.-P., Brennan, B., Pollard, A., & Hofmann, S. (2019) · Journal of Physical Chemistry C · doi:10.1021/acs.jpcc.9b03808 · Cited by 28 · cited 7×
“This small 2%–5% conductivity increase is at the same order of magnitude but slightly higher than what was reported in an earlier work using direct electrical measurements on a 44 80lm2 patch of CVD graphene on SiO2/Si wafer support.”
BackgroundMethodInfluentialSelf-citationAn international intercomparison of THz time-domain spectrometers
Naftaly, M. (2016) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz.2016.7758763 · Cited by 23 · cited 1× · see citing works
“The slight discrepancy may be due to sample surface related imperfections, leading to scattering losses and measurement using a focused beam as opposed to a collimated beam [25].”
BackgroundModelling of sub-wavelength THz sources as Gaussian apertures.
Lin, H., Fumeaux, C., Fischer, B., & Abbott, D. (2010) · Optics Express · doi:10.1364/oe.18.017672 · Cited by 23 · see citing works
Self-citationComprehensive modeling of THz microscope with a sub-wavelength source.
Lin, H., Fumeaux, C., Ung, B. S. Y., & Abbott, D. (2011) · Optics Express · doi:10.1364/oe.19.005327 · Cited by 11
Self-citation
Flagged first, then by citations
2 of the 34 references couldn’t be matched to a known paper.
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From Terahertz Imaging to Terahertz Wireless Communications
Huang, Y., Shen, Y., & Wang, J. (2022) · Engineering · doi:10.1016/j.eng.2022.06.023 · Cited by 316 · see citing works
Ludlam, G. A. H., Gnaniah, S. J. P., Degl’Innocenti, R., Gupta, G., Wain, A. J., & Lin, H. (2024) · ACS Sustainable Chemistry & Engineering · doi:10.1021/acssuschemeng.4c01820 · Cited by 32 · see citing works
Self-citationCase studies of electrical characterisation of graphene by terahertz time-domain spectroscopy
Whelan, P. R., Zhou, B.-B., Bezencenet, O., Shivayogimath, A., Mishra, N., Shen, Q., Jessen, B. S., Pasternak, I., Mackenzie, D. M. A., Ji, J., et al. (2021) · 2D Materials · doi:10.1088/2053-1583/abdbcb · Cited by 27 · see citing works
Alves-Lima, D., Li, X.-R., Coulson, B., Nesling, E., Ludlam, G., Degl'Innocenti, R., Dawson, R., Peruffo, M., & Lin, H. (2022) · Social Science Research Network · doi:10.2139/ssrn.3993219 · Cited by 19 · see citing works
“Advances made in THz-TDS have opened up many exciting industrial applications [35 – 39] where compared to aforementioned methods in PEMs testing, THz-TDS has been demonstrated to probe molecular water states non-destructively, without specialised sample preparation and without physical contact,…”
Self-citationReference-free THz-TDS conductivity analysis of thin conducting films.
Whelan, P. R., Shen, Q., Luo, D., Wang, M.-H., Ruoff, R., Jepsen, P., Bøggild, P., & Zhou, B.-B. (2020) · Optics Express · doi:10.1364/oe.402447 · Cited by 19 · see citing works
Porosity characterisation of solid-state battery electrolyte with terahertz time-domain spectroscopy
Kiritharan, S., Lucas, S., Degl'Innocenti, R., Hua, X., Dawson, R., & Lin, H. (2024) · Journal of Power Sources · doi:10.1016/j.jpowsour.2024.234050 · Cited by 16 · see citing works
Self-citationArtesani, A., Lamuraglia, R., Menegazzo, F., Bonetti, S., & Traviglia, A. (2022) · Applied Spectroscopy · doi:10.1177/00037028221133404 · Cited by 14 · see citing works
Starinskiy, S., Safonov, A., Sulyaeva, V., Rodionov, A., Shukhov, Y., & Bulgakov, A. (2020) · doi:10.1016/j.tsf.2020.138392 · Cited by 12
Alves-Lima, D., Williams, B. M., Schlegl, H., Gupta, G., Letizia, R., Dawson, R., & Lin, H. (2022) · Fuel Cells · doi:10.1002/fuce.202200030 · Cited by 9 · see citing works
Self-citationInterface engineered germanium for infrared THz modulation
Li, Y.-P., Zhang, D.-N., Liao, Y.-L., Wen, Q., Zhong, Z., & Wen, T.-L. (2020) · doi:10.1016/j.optmat.2020.110659 · Cited by 7
Zhou, B., Rasmussen, M., Whelan, P. R., Ji, J., Shivayogimath, A., Bøggild, P., & Jepsen, P. U. (2023) · Sensors · doi:10.3390/s23073669 · Cited by 9 · see citing works
Rapid THz time-of-flight imaging on single layer graphene for conductivity assessment
Kim, Y., Yim, J., Khan, A., Kim, J., & Ahn, Y. (2024) · Infrared Physics & Technology · doi:10.1016/j.infrared.2024.105201 · Cited by 4 · see citing works
Terahertz time domain spectroscopy data processing: analysing uncertainties to push boundaries
Lavancier, M., Eliet Barois, S., Denakpo, E., Vlieghe, J., Vindas, N., Hindle, F., Cuisset, A., & Peretti, R. (2022) · Terahertz Photonics II · doi:10.1117/12.2620069 · Cited by 2 · see citing works
“enabled myriads of applications from semiconductor spectroscopy [5, 6], 2D materials [7], liquids [8], biological samples”
BackgroundWenzel, K., Breuer, S., Kleinkamp, A., Dohms, A., Heßelmann, T., Keyvaninia, S., Schell, M., Kohlhaas, R., & Liebermeister, L. (2026) · IEEE Transactions on Terahertz Science and Technology · doi:10.1109/tthz.2026.3693845 · Cited by 1
“For conductive samples this has been applied to graphene in reflection [17], [18] as well as in transmission geometry [19].”
Tofani, S., Fuscaldo, W., Ritacco, T., Beccherelli, R., & Zografopoulos, D. C. (2025) · IEEE Transactions on Terahertz Science and Technology · doi:10.1109/tthz.2025.3629861 · Cited by 1 · see citing works
“Key studies, including [6] and [7], employ high-resistivity silicon as a reference to address phase sensitivity issues related to metal mirrors [8], [9], [10].”
France, G. A. H., Mohammadpour, M., Degl’Innocenti, R., Peruffo, M., & Lin, H. (2025) · IEEE Transactions on Terahertz Science and Technology · doi:10.1109/tthz.2025.3594070 · Cited by 2 · see citing works
“The advent of terahertz sensing has opened up many exciting applications [35], [36], [37], where the sensitivity to water [38], [39], [40] has motivated investigations into PFSAs [41], [42], [43], [44], [45] using terahertz time-domain spectroscopy (THz-TDS) to rapidly and noninvasively probe water…”
Self-citationDensity characterisation of solid-state electrolytes using terahertz time-domain spectroscopy
Kiritharan, S., Degl’Innocenti, R., Bawuah, P., Engelbrecht, S., Fischer, B., Hua, X., Dawson, R., & Lin, H. (2025) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz61557.2025.11319948 · Cited by 1
“Advances made in THz sensing have opened up many exciting applications, including gas detection and diagnostic imaging of melanomas, [4], [5], [6], [7], [8] and in particular for studying energy materials such as Nafion membranes [9], [10].”
Self-citationLudlam, G., Gnaniah, S. J. P., Degl'Innocenti, R., Gupta, G., Wain, A. J., & Lin, H. (2024) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz60956.2024.10697715 · Cited by 1
Self-citationEbrahimzadeh, R., Gigoyan, S., Xiao, G., Lang, S., Entezami, M., Farahabadi, S. A. H., & Nezhad-Ahmadi, M. R. (2026) · IEEE Journal of Radio Frequency Identification · doi:10.1109/jrfid.2026.3702586 · Cited by 1
“In [21] has been focused on simultaneous extraction of optical constants and thickness with deep-subwavelength precision using THz-TDS, while the study in [22] investigated through-substrate reflection THz-TDS for graphene conductivity mapping.”
Robust phase correction techniques for terahertz time-domain reflection spectroscopy
Jatkar, K. D., Yeh, T.-T., Pancaldi, M., & Bonetti, S. (2024) · arXiv · doi:10.48550/arxiv.2412.18662
“[18, 19, 25, 26].”
Burton, O., Engelbrecht, S., Goepfert, T., Abbasi, I. H., Xin, L.-Y., Fischer, B. M., Joyce, H., Hofmann, S., & Lin, H. (2026) · ACS Nano · doi:10.1021/acsnano.6c03948
Self-citationLudlam, G., Gnaniah, S. J. P., Degl'Innocenti, R., Gupta, G., Wain, A. J., & Lin, H. (2024) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz60956.2024.10697721
“THz-TDS is an exciting technique [3,4] with demonstrated sensitivity to water [5–7] and has previously been shown to resolve water states under ambient conditions [2,8,9].”
BackgroundSelf-citationLudlam, G., de Lima, D. F. A., Li, X., Coulson, B., Nesling, E., Degl'Innocenti, R., Dawson, R., Peruffo, M., & Lin, H. (2022) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz50927.2022.9895912
“THz has quickly been gaining popularity for material characterisation [3-7] and THz-TDS has been shown to resolve water states of these membranes at thickness of ~170 μm noninvasively [1].”
BackgroundSelf-citationWater States Analysis of Anion Exchange Membranes with Terahertz Time-Domain Spectroscopy
Frow, J. J., Periasamy, A., Gupta, G., Varcoe, J., & Lin, H. (2022) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz50927.2022.9895705
“Sensing using terahertz radiation is fast gaining popularity [5-9].”
Self-citationEnvironmental graphene conductivity sensing using terahertz time-domain reflection spectroscopy
Lin, H., Burton, O., Engelbrecht, S., Tybussek, K., Fischer, B., & Hofmann, S. (2020) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz46771.2020.9370983
“We have demonstrated the feasibility and potential of measuring the electrical conductivity of CVD graphene through the supporting substrate using THz-TDS in reflection geometry, where the supporting substrate can simultaneously function as a viewing window to an environment designed to modify graphene's electrical pr…”
BackgroundResultSelf-citationLi, X., Bawuah, P., Williams, B. M., Zeitler, J., & Lin, H. (2020) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz46771.2020.9370477
“Sensing using the terahertz radiation is fast gaining popularity [5-9].”
BackgroundSelf-citationAlves-Lima, D., Schlegl, H., Williams, B. M., Letizia, R., Dawson, R., & Lin, H. (2020) · International Conference on Infrared, Millimeter, and Terahertz Waves · doi:10.1109/irmmw-thz46771.2020.9370456
“Terahertz (THz) radiation has been growing in popularity for contactless and non-destructive testing across various industrial sectors [2-7].”
BackgroundSelf-citation
- Authors
- Lin, H., Burton, O. J., Engelbrecht, S., Tybussek, K.-H., Fischer, B. M., & Hofmann, S.
- Affiliations
- Lancaster University (GB)
- University of Cambridge (GB)
- Institut Franco-Allemand de Recherches de Saint-Louis (FR)
- Corresponding author
- Lin, Hungyen
- Venue
- Applied Physics Letters
- Publisher
- AIP Publishing
- Published
- 2020-01-13
- Volume
- 116
- Issue
- 2
- ISSN
- 0003-6951 (ISSN-L)
- 1077-3118
- OpenAlex
- W2999484451
- Cited by
- 31
- References
- 34
- Citations by year
- 2026: 3 · 2025: 3 · 2024: 5 · 2023: 1 · 2022: 9 · 2021: 4 · 2020: 6
- FWCI
- 1.72
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Applied Physics Letters (publishedVersion, cc-by)
- Lancaster EPrints (Lancaster University) (submittedVersion)
- Cambridge University Engineering Department Publications Database (submittedVersion)
- Funders
- Engineering and Physical Sciences Research Council (EP/R019460/1, EP/K016636/1)
- Topics
- Physical Sciences › Engineering › Electrical and Electronic Engineering › Terahertz technology and applications
- Physical Sciences › Materials Science › Materials Chemistry › Graphene research and applications
- Physical Sciences › Engineering › Electrical and Electronic Engineering › Microwave and Dielectric Measurement Techniques
- Keywords
- terahertz time-domain spectroscopy, reflection geometry, CVD graphene, silicon substrate, in situ measurement, operando measurement, environmental cell, large-area graphene films
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