https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/ The latest from Physics » Ultrafast & Terahertz Photonics: Publications en-GB (C) 2026 University of Warwick Tue, 28 Apr 2026 12:37:45 GMT http://blogs.law.harvard.edu/tech/rss SiteBuilder2, University of Warwick, http://go.warwick.ac.uk/sitebuilder 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 biomedical highlight Lloyd-Hughes MacPherson Milot nanomaterials perovskites photoluminescence review semiconductors THz components THz imaging THz spectroscopy ultrafast Untagged https://pubs.acs.org/doi/10.1021/acs.jpclett.6c00718 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/currie2026.png?maxWidth=200" alt="Vibrations" style="margin-right: 10px;" border="0" align="right" /></p> <p><strong>A. Currie</strong>, J. Liu, <strong>J.M. Woolley</strong>, and <strong>J. Lloyd-Hughes</strong>, <br />J. Phys. Chem. Lett. <strong>-</strong> - <span class="citation_volume"></span><strong><span class="cit-volume"></span></strong><span class="cit-issue"> </span><span class="cit-pageRange"></span><strong><span class="citation_volume"></span></strong> (Apr 2026) <button class="abstractButton" onclick="location.href='https://doi.org/10.1021/acs.jpclett.6c00718';">web</button> <button class="abstractButton" onclick="location.href='https://pubs.acs.org/doi/pdf/10.1021/acs.jpclett.6c00718?ref=article_openPDF';">pdf</button> <button class="abstractButton" onclick="showHide('currie2026')">Show abstract</button></p> <div id="currie2026" style="display: none;">Phonon engineering has improved charge transport in semiconducting organic molecules by introducing high mass side chains, which ameliorate harmful transient localization. The influence of these side chains on thermal energy transfer and dynamic disorder has not been fully explored. In this work, we first use low temperature X-ray diffraction to probe thermally induced structural changes in functionalized acene molecular semiconductors, combined with low temperature IR spectroscopy to track changes to their vibrational energy landscape. Furthermore, time-resolved IR pump&ndash;IR probe spectroscopy is employed to measure IR absorption kinetics associated with the high mass side chains of molecules, revealing intramolecular vibrational energy redistribution pathways. Alkyne groups in the side chains are shown to act as vibrational energy traps, remaining hot for time scales of &gt;2 ns. The results reveal nonequilibrium vibrational pathways associated with side chains that may influence the phonon manifold relevant to dynamic disorder.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1021/acs.jpclett.6c00718&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1021/acs.jpclett.6c00718" data-hide-no-mentions="true"></div> Lloyd-Hughes ultrafast semiconductors 2026 Tue, 28 Apr 2026 12:36:00 GMT 8ac672c49dcce476019dd4176e591126 https://doi.org/10.1063/5.0319459 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Ou2026.jpg?maxWidth=200" alt="Diagram" style="margin-right: 20px;" border="0" align="right" /></p> <p><strong>H. Ou, E. Pickwell-MacPherson</strong> and <strong>J. Lloyd-Hughes</strong> <br />J. Appl. Phys. <strong>139</strong>, 123101 (Mar 2026) <button class="abstractButton" onclick="location.href='https://doi.org/10.1063/5.0319459';">web</button> <button class="abstractButton" onclick="location.href='https://pubs.aip.org/aip/jap/article-pdf/doi/10.1063/5.0319459/20954442/123101_1_5.0319459.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Ou2026')">Show abstract</button></p> <div id="Ou2026" style="display: none;">Generalized ellipsometry can uncover the optical properties of anisotropic materials, in which the light&ndash;matter interaction alters the polarization state. In the terahertz frequency range, generalized ellipsometry has been infrequently realized due to the challenge of rapidly controlling and measuring THz polarization. Here, we report the development and calibration of a high-efficiency terahertz time-domain generalized ellipsometer based on two dual-channel photoconductive antennas. The fiber-coupled multi-pixel devices act as source and detector and achieve a high data throughput with four independent terahertz pulses in a single optical delay scan, without the need for any bulky or slow polarization elements such as polarizers. Following a one-off system calibration, an accurate optical characterization of a uniaxially birefringent Al₂O₃ crystal serves to validate the method. Our technique benefits from efficient data throughput, full polarization-resolved capability, and reduced system complexity, paving the way to in situ and real-time monitoring applications.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1063/5.0319459" data-hide-no-mentions="true"></div> <div><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1063/5.0319459&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> THz spectroscopy THz components MacPherson Lloyd-Hughes 2026 Mon, 30 Mar 2026 08:07:58 GMT 8ac672c59d1fb7fa019d3dc90a5c7a26 https://iopscience.iop.org/article/10.1088/2515-7647/ae4b7a/meta <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Agarwal2026.jpg?maxWidth=150" alt="THz scab" style="margin-right: 10px;" border="0" align="right" /></p> <p class="mb-0"><strong>A. Agarwal</strong> and <strong>E. Pickwell-MacPherson</strong></p> <p>J. Phys. Photonics <strong>8</strong> 011001 <span class="cit-pageRange"> </span>(Mar 2026) <button class="abstractButton" onclick="location.href='https://dx.doi.org/10.1088/2515-7647/ae4b7a';">web</button> <button class="abstractButton" onclick="location.href='https://iopscience.iop.org/article/10.1088/2515-7647/ae4b7a/pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Agarwal2026')">Show abstract</button></p> <div id="Agarwal2026" style="display: none;">Terahertz (THz) sensing has gained significant attention as a non-ionizing modality capable of probing the superficial layers of biological tissue with high sensitivity to water content, structural changes, and biochemical composition. Its strong interaction with water makes it uniquely suited for investigating dermatological applications such as hydration assessment, wound and burn monitoring, and the detection and characterization of skin cancers. However, the shallow penetration depth of THz light, combined with the sensitivity of measurements to probe-skin coupling, contact pressure, and motion artifacts, poses persistent challenges for in vivo use. Overcoming these limitations requires carefully engineered hardware, robust measurement protocols, and advanced computational techniques tailored to biological variability. This article reviews the evolution of THz instrumentation for in vivo skin sensing, spanning early laboratory systems to emerging compact, handheld, robotic, and computationally enhanced platforms. Key developments in probe miniaturization, ergonomic design, and automated control of probe orientation and pressure are described, as these advances directly influence measurement reproducibility and clinical usability. We highlight recent progress in single-pixel imaging, which offers video-rate capabilities, the emergence of waveguide-integrated metamaterial sensors that push spatial resolution far below the diffraction limit, and THz ellipsometry that gives complementary contrast. In addition, we discuss the growing role of data-driven processing, compressed-sensing algorithms, and biophysical modeling in extracting clinically relevant parameters from THz measurements. Although promising, many of the emerging systems remain untested in in vivo dermatological scenarios, and challenges including motion artifacts, calibration stability, and inter-subject variability must be addressed. Continued interdisciplinary work between engineers, physicists, and clinicians is essential for transitioning THz systems toward practical, patient-compliant diagnostic tools.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1088/2515-7647/ae4b7a&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1088/2515-7647/ae4b7a" data-hide-no-mentions="true"></div> THz spectroscopy MacPherson THz imaging biomedical 2026 Mon, 30 Mar 2026 07:58:00 GMT 8ac672c49d3cb3aa019d3dbff27b01be https://www.nature.com/articles/s41467-026-68290-x <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Mou2026.png?maxWidth=150" alt="THz scab" style="margin-right: 10px;" border="0" align="right" /></p> <p class="mb-0"><strong>S. Mou, R.I. Stantchev</strong>, S. Saxena, <strong>H. Ou, S. Rane</strong>, S. Pain, J.D. Murphy, E. Hendry, <strong>J. Lloyd-Hughes</strong> and <strong>E. Pickwell-MacPherson</strong></p> <p>Nature Communications <strong>17</strong> 1571 <span class="cit-pageRange"> </span>(Jan 2026) <button class="abstractButton" onclick="location.href='https://www.nature.com/articles/s41467-026-68290-x';">web</button> <button class="abstractButton" onclick="location.href='https://www.nature.com/articles/s41467-026-68290-x.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Mou2026')">Show abstract</button></p> <div id="Mou2026" style="display: none;">Real-time, non-invasive imaging techniques are essential for advancing biomedical diagnostics and material analysis, yet existing terahertz (THz) systems often suffer from limited speed, bulky designs, and poor adaptability to in situ environments. Addressing these challenges, we present a fully fibre-coupled THz attenuated total internal reflection single-pixel imaging system, offering a compact, flexible, and robust platform for non-destructive spectroscopy and in vivo imaging. This all-fibre architecture enables seamless integration for in situ biomedical applications, including measurements directly on patients. Central to our design is a THz spatial light modulator based on an unpassivated silicon wafer, facilitating high-speed modulation and enabling video-rate imaging with a spatial resolution down to 360 μm. Despite being in the reflection geometry and using fibre-coupled light, our system achieves an imaging throughput exceeding 30,000 pixels per second for 64-by-64 images - over five-fold higher than the state of the art - representing a substantial improvement in real-time THz imaging capabilities.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1038/s41467-026-68290-x&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1038/s41467-026-68290-x" data-hide-no-mentions="true"></div> THz spectroscopy MacPherson Lloyd-Hughes THz imaging biomedical highlight 2026 Wed, 25 Feb 2026 12:24:00 GMT 8ac672c59c8dd0ec019c94c1d08c39b5 https://advanced.onlinelibrary.wiley.com/doi/10.1002/adom.202402011 <div class="news-thumbnail" style="float: left; margin-right: 10px; margin-bottom: 5px;"><img class="thumbnail" width="100" height="100" src="https://warwick.ac.uk/sitebuilder2/file/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications?sbrPage=%2Ffac%2Fsci%2Fphysics%2Fresearch%2Fcondensedmatt%2Fultrafastphotonics%2Fpublications&newsItem=8ac672c59b07d9a6019b1cce8b5e2b05" alt="image"></div><p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Hutchinson2025.png?maxWidth=150" alt="2D-3D" style="margin-right: 10px;" border="0" align="right" /></p> <p class="mb-0"><strong>Jake D. Hutchinson</strong>, Marcin Giza, <strong>Nathaniel P. Gallop</strong>, Benjamin Vella, <strong>Edward Butler-Caddle, Shaoyang Wang, James Lloyd-Hughes,</strong> Pablo Docampo and <strong>Rebecca L Milot</strong></p> <p>Adv. Optical Materials <strong>13</strong> e02011 <span class="cit-pageRange"> </span>(Dec 2025) <button class="abstractButton" onclick="location.href='https://advanced.onlinelibrary.wiley.com/doi/10.1002/adom.202402011';">web</button> <button class="abstractButton" onclick="location.href='https://advanced.onlinelibrary.wiley.com/doi/epdf/10.1002/adom.202402011';">pdf</button> <button class="abstractButton" onclick="showHide('Hutchinson2025')">Show abstract</button></p> <div id="Hutchinson2025" style="display: none;">The incorporation of Ruddlesden&ndash;Popper (RP)/3D perovskite heterostructures into photovoltaic cells has been shown to increase both the efficiency and stability of the devices. Here, a series of methylammonium lead triiodide (MAPbI3) thin films treated with varying 2-phenylethylammonium (PEA) concentrations are investigated with static and ultrafast spectroscopic techniques to reveal the mechanisms of the observed performance benefits. Transient absorption spectroscopy is employed to elucidate the effect of a surface RP layer on the excited state of the MAPbI3 films and reveal that several different RP structures are formed and participate in the charge-carrier dynamics. The passivation effects of PEA are investigated with optical pump&ndash;terahertz probe (OPTP) experiments using a variety of excitation conditions to simultaneously probe the surface and bulk recombination dynamics. Fitting models to the OPTP data for each excitation scheme allows the material parameters that govern the ultrafast dynamics to be quantified. It is found that as the PEA concentration increases, the surface recombination velocity exhibits a monotonic decrease, suggesting the RP layer is effective at passivating surface traps. Furthermore, the bulk monomolecular recombination rate is also found to decrease with the addition of PEA, indicating that the benefits of this passivation approach are not limited to the upper surface of the MAPbI3 films.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1002/adom.202402011" data-hide-no-mentions="true"></div> THz spectroscopy Milot perovskites Lloyd-Hughes ultrafast highlight 2025 Sun, 14 Dec 2025 12:20:00 GMT 8ac672c59b07d9a6019b1cce8b5e2b05 https://journals.aps.org/prl/abstract/10.1103/mvdf-bdrx <div class="news-thumbnail" style="float: left; margin-right: 10px; margin-bottom: 5px;"><img class="thumbnail" width="100" height="100" src="https://warwick.ac.uk/sitebuilder2/file/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications?sbrPage=%2Ffac%2Fsci%2Fphysics%2Fresearch%2Fcondensedmatt%2Fultrafastphotonics%2Fpublications&newsItem=8ac672c59ab66a70019ab7d8e2bb0527" alt="image"></div><p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/keat2025.png?maxWidth=200" alt="Shaping" style="margin-right: 10px;" border="0" align="right" /></p> <p><strong>T.J. Keat</strong>, J. Zhao, <strong>J.M. Woolley</strong>, P. Malakar, G.M. Greetham, X. Wu, J.P. Goss, R.J. Cruddace, C.B. Hartland, M.W. Dale, V.G. Stavros, M.E. Newton and <strong>J. Lloyd-Hughes</strong>, <br />Phys. Rev. Lett. <strong>135</strong> 216902 <span class="citation_volume"></span><strong><span class="cit-volume"></span></strong><span class="cit-issue"> </span><span class="cit-pageRange"></span><strong><span class="citation_volume"></span></strong> (Nov 2025) <button class="abstractButton" onclick="location.href='https://doi.org/10.1103/mvdf-bdrx';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/keat2025.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('keat2025')">Show abstract</button></p> <div id="keat2025" style="display: none;">We investigated ultrafast defect-lattice dynamics in diamond using the N_s:H−C⁰ defect, an analog of bond-centered hydrogen in semiconductors. Combining synthesis, ultrafast vibrational spectroscopy, and ab initio calculations, we show that excitation of the defect’s stretch mode leads to the generation of localized phonons and the formation of a hot ground state, where the interatomic potential is transiently modified. Our results reveal unexpected nonequilibrium phonon effects despite diamond’s exceptionally high thermal conductivity, with implications for quantum defect engineering.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1103/mvdf-bdrx&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1103/mvdf-bdrx" data-hide-no-mentions="true"></div> nanomaterials Lloyd-Hughes ultrafast highlight 2025 Tue, 18 Nov 2025 00:20:00 GMT 8ac672c59ab66a70019ab7d8e2bb0527 https://link.springer.com/article/10.1007/s10762-025-01055-7 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/jacob2025.webp?maxWidth=200" alt="Diagram" style="margin-right: 20px;" border="0" align="right" /></p> <p><strong>J.J. Young, A. Agarwal, B.G. Page, A. Dogra, A.I. Hernandez-Serrano, </strong> J. Hardwicke and <strong>E. Pickwell-MacPherson</strong> <br />J. IR mm THz waves <strong>46</strong>, 36 (May 2025) <button class="abstractButton" onclick="location.href='https://doi.org/10.1007/s10762-025-01055-7';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Jacob2025.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Jacob2025')">Show abstract</button></p> <div id="Jacob2025" style="display: none;">In this work, we demonstrate significant modifications to our robotically controlled terahertz (THz) sensing system, the “PicoBot,” enabling it to perform in vivo imaging of skin rather than limiting it to single-point measurements. By integrating a robotic arm equipped with force-sensitive feedback control, we maintain consistent contact pressure between the probe and the skin surface throughout imaging. In conjunction with this hardware advancement, we introduce an accompanying image analysis pipeline that reduces noise and enhances repeatability across scans. These improvements allow for reliable intra- and inter-subject comparisons, a critical step toward the clinical utility of THz imaging. Our ultimate aim is to use THz imaging to detect skin cancer margins: this paper highlights progress towards this goal and skin evaluation in general.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1007/s10762-025-01055-7" data-hide-no-mentions="true"></div> <div><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1007/s10762-025-01055-7&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> MacPherson THz imaging biomedical highlight 2025 Fri, 30 May 2025 13:50:00 GMT 8ac672c7980c09a7019813885e952e31 https://doi.org/10.1007/s10762-025-01052-w <div class="news-thumbnail" style="float: left; margin-right: 10px; margin-bottom: 5px;"><img class="thumbnail" width="100" height="100" src="https://warwick.ac.uk/sitebuilder2/file/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications?sbrPage=%2Ffac%2Fsci%2Fphysics%2Fresearch%2Fcondensedmatt%2Fultrafastphotonics%2Fpublications&newsItem=8ac672c796c9abed0196d9ef865d0393" alt="image"></div><p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/lloyd-hughes2025.png?maxWidth=200" alt="Shaping" style="margin-right: 10px;" border="0" align="right" /></p> <p><strong>J. Lloyd-Hughes</strong>, <strong>N. Chopra</strong>, <strong>J. Deveikis</strong>, R. Pandya and <strong>J. Woolley</strong> <br />J. Infrared mm THz <strong>46</strong> 34 <span class="citation_volume"></span><strong><span class="cit-volume"></span></strong><span class="cit-issue"> </span><span class="cit-pageRange"></span><strong><span class="citation_volume"></span></strong> (May 2025) <button class="abstractButton" onclick="location.href='https://doi.org/10.1007/s10762-025-01052-w';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/lloyd-hughes2025.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('lloyd-hughes2025')">Show abstract</button></p> <div id="lloyd-hughes2025" style="display: none;">Electro-optic sampling allows the electric field of THz, mid-infrared and visible light pulses to be measured directly as a function of time, with data analysis often performed in the frequency domain after fast Fourier transform. Here, we review aspects of Fourier theory relevant to the frequency-domain analysis of light pulses recorded in the time domain. We describe a “best practise” approach to using the discrete Fourier transform that ensures consistency with analytical results from the continuous Fourier transform. We summarise a phenomenological time-domain model of THz pulses, based on carrier and envelope waves, and show that it can reproduce a wide variety of experimental single- to multi-cycle THz pulses, with exemplary data from lab-based sources (photoconductive antennae, optical rectification, spintronic emitters) and a THz free-electron laser. A quantitative comparison of the spectral energy density of these distinct sources is enabled by the amplitude-accurate discrete Fourier transform. We describe a method that ensures the accurate calculation of the absolute spectral phase (valid for arbitrary sampling windows in the time domain) and summarise how the carrier-envelope phase, pulse arrival time, and chirp can be obtained from the phase. Our aim with this overview of THz pulse analysis is to highlight algorithms and concepts that are useful to newcomers to time-domain spectroscopy and experts, alike.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1007/s10762-025-01052-w&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1007/s10762-025-01052-w" data-hide-no-mentions="true"></div> THz components Lloyd-Hughes ultrafast review highlight 2025 Fri, 16 May 2025 16:31:00 GMT 8ac672c796c9abed0196d9ef865d0393 https://ieeexplore.ieee.org/document/10982400 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/ben2025.gif?maxWidth=200" alt="Diagram" style="margin-right: 20px;" border="0" align="right" /></p> <p><strong>B.G. Page, J.J. Young, A.I. Hernandez-Serrano, </strong> J. Hardwicke and <strong>E. Pickwell-MacPherson</strong> <br />IEEE Trans. THz Sci. Tech. <strong>15</strong>, 573 (May 2025) <button class="abstractButton" onclick="location.href='https://doi.org/10.1109/TTHZ.2025.3566562';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/ben2025.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Ben2025')">Show abstract</button></p> <div id="Ben2025" style="display: none;">Eczema and psoriasis are two of the most prevalent skin conditions in the United Kingdom. Typically, diagnosis and treatment assessment are evaluated based on qualitative measures such as skin appearance and patient feedback. Thus, there is a need for a robust and quantitative method of assessing treatment efficacy and monitoring improvements in skin condition. Terahertz (THz) sensing is a promising candidate, owing to its nonionising properties and high water sensitivity. However, THz sensing is heavily reliant upon signal processing techniques, in particular deconvolution methods used to extract skin-dependent parameters. Conventionally, double Gaussian deconvolution has been used, however this has been shown to oversmooth data and cause unnecessary signal suppression. In this study, an alternative approach, known as frequency-wavelet domain deconvolution, has been applied to in vivo THz skin measurements obtained in a clinical study. It is shown that this deconvolution method significantly enhances the usable signal, and improves the accuracy of the extracted impulse response function.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1109/TTHZ.2025.3566562" data-hide-no-mentions="true"></div> <div><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1109/TTHZ.2025.3566562&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> THz spectroscopy MacPherson biomedical 2025 Fri, 02 May 2025 09:50:00 GMT 8ac672c49809b12801981373f93f6d60 https://pubs.aip.org/aip/app/article/10/5/056101/3345527/Terahertz-harmonic-generation-and-nonlinear <div class="news-thumbnail" style="float: left; margin-right: 10px; margin-bottom: 5px;"><img class="thumbnail" width="100" height="100" src="https://warwick.ac.uk/sitebuilder2/file/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications?sbrPage=%2Ffac%2Fsci%2Fphysics%2Fresearch%2Fcondensedmatt%2Fultrafastphotonics%2Fpublications&newsItem=8ac672c59686280d01968d5587b162e0" alt="image"></div><p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/riccardo2025.jpg?maxWidth=200" alt="Shaping" style="margin-right: 10px;" border="0" align="right" /></p> <p>R. Degli'Innocenti, Y. Lu, A.M. Zaman, <strong>J.M. Woolley, N. Chopra,</strong> W. Tadbier, W. Michailow, S. Hofmann and <strong>J. Lloyd-Hughes</strong> <br />APL Photonics <strong>10</strong> 056101 (May 2025) <button class="abstractButton" onclick="location.href='https://doi.org/10.1063/5.0264305';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/riccardo2025.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('riccardo2025')">Show abstract</button></p> <div id="riccardo2025" style="display: none;">We report on the terahertz (THz) harmonic generation in an active graphene/metamaterial device by using powerful ultrafast table-top THz time-domain spectroscopic systems. Complex nonlinear transmission spectra, comprising even and odd harmonics, emerge when the devices are tested with intense ultrafast THz pulses with peak electric fields in the range of 1&ndash;150 kV/cm. The odd and even harmonic features show a positive correlation with carrier concentration, allowing for efficient frequency tuning on top of tunable group delay dispersion. Interestingly, before the onset of saturation, observed at 20&ndash;25 kV/cm, the main resonance and the harmonic features exhibit an anti-crossing trend that can be further exploited for active frequency tuning. These results report a key milestone for the fundamental investigation of the nonlinearity of 2D materials. At the same time, they represent an important advance in the design of future integrated THz optoelectronics by providing novel functionalities for THz light generation and manipulation.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1063/5.0264305&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1063/5.0264305" data-hide-no-mentions="true"></div> THz spectroscopy nanomaterials Lloyd-Hughes 2025 Thu, 01 May 2025 19:31:00 GMT 8ac672c59686280d01968d5587b162e0