https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/ The latest from Physics » Ultrafast & Terahertz Photonics: Publications (tag [highlight]) 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://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://pubs.acs.org/doi/10.1021/acs.langmuir.4c03103 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Goncalo2024.gif?maxWidth=50" alt="Diagram" style="margin-right: 20px;" border="0" align="right" /></p> <p><strong>G. Costa, </strong> E.M. Brogden, <strong>J.J. Young, H. Ou, A.I. Hernandez-Serrano, R. I. Stantchev,</strong> Stefan A.F. Bon and <strong>E. Pickwell-MacPherson</strong> <br />Langmuir <strong>40</strong>, 25023 (Nov 2024) <button class="abstractButton" onclick="location.href='https://doi.org/10.1021/acs.langmuir.4c03103';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Goncalo2024.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Goncalo2024')">Show abstract</button></p> <div id="Goncalo2024" style="display: none;">The dynamics of the drying process of polymer latexes after casting as a wet film onto a substrate are important to track as they influence the physical and mechanical properties and performance of the dried polymer films. Current methods used to follow this drying process include gravimetric analysis, coupled with advanced techniques like GARField-NMR or optical coherence tomography. The latter two methods provide height and spatial information in the z-direction, normal to the substrate, and occasionally in the xz- or yz-planes. Terahertz time-domain spectroscopy (THz-TDS) is a welcome addition as it provides both the structural and spectroscopic information in the parallel xy-plane, filling the geometric gap. Herein, we utilize THz-TDS to study the drying and film formation process of various polymer latexes with a broad range of glass transition temperatures. We showcase the applicability of this technique in obtaining 2D parallel hydration maps of the drying dispersions, in the form of droplets, using latex-dependent calibration lines. Our findings display known phenomena arising from the drying of the colloidal dispersions.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1021/acs.langmuir.4c03103" data-hide-no-mentions="true"></div> <div><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1021/acs.langmuir.4c03103&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> THz spectroscopy MacPherson 2024 highlight Wed, 13 Nov 2024 13:45:00 GMT 8ac672c7980c09a70198134e2fe4222e https://pubs.acs.org/doi/10.1021/acs.jpcc.4c03221 <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=8a17841b910d330101912470859000c0" alt="image"></div><p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Deveikis2024.jpeg?maxWidth=150" alt="ThMAPbI" style="margin-right: 10px;" border="0" align="right" /></p> <p><span class="accordion-tabbed__tab-mobile accordion__closed"><strong>Justas Deveikis</strong>, Marcin Giza, David Walker, Jie Liu, Claire Wilson, <strong>Nathaniel P. Gallop</strong>, Pablo Docampo, <strong>James Lloyd-Hughes</strong> and <strong>Rebecca L. Milot</strong></span><br />J. Phys. Chem. C <span class="citation_volume"><strong>128 </strong></span>13108<span class="cit-issue"></span><span class="cit-issue"><strong><span class="cit-volume"></span></strong><span class="cit-issue">&nbsp;</span></span><span class="cit-pageRange"> </span>(July 2024) <button class="abstractButton" onclick="location.href='https://doi.org/10.1021/acs.jpcc.4c03221';">web</button> <button class="abstractButton" onclick="location.href='deveikis2024.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Deveikis2024')">Show abstract</button></p> <div id="Deveikis2024" style="display: none;">Improved knowledge of the influence of temperature upon layered perovskites is essential to enable perovskite-based devices to operate over a broad temperature range and to elucidate the impact of structural changes upon the optoelectronic properties. We examined the Ruddlesden&ndash;Popper layered perovskite 2-thiophenemethylammonium lead iodide (ThMA2PbI4) and observed a structural phase transition between a high- and a low-temperature phase at 220&thinsp;K using temperature-dependent X-ray diffraction, UV&ndash;visible absorption, and photoluminescence (PL) spectroscopy. The structural phase transition altered the tilt pattern of the inorganic octahedra layer, modifying the absorption and PL spectra. Further, we found a narrow and intense additional PL peak in the low-temperature phase, which we assigned to radiative emission from a defect-bound exciton state. In both phases we determined the thermal expansion coefficient and found values similar to those of cubic 3D perovskites, i.e., larger than those of typical substrates such as glass. These results demonstrate that the organic spacer plays a critical role in controlling the temperature-dependent structural and optoelectronic properties of layered perovskites and suggests more widely that strain management strategies may be needed to fully utilize layered perovskites in device applications.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1021/acs.jpcc.4c03221" data-hide-no-mentions="true"></div> photoluminescence Milot 2024 perovskites Lloyd-Hughes highlight Mon, 05 Aug 2024 21:27:00 GMT 8a17841b910d330101912470859000c0 https://opg.optica.org/boe/fulltext.cfm?uri=boe-15-5-3064&id=549001 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/arturo2024.jpeg?maxWidth=200" alt="Diagram" style="margin-right: 20px;" border="0" align="right" /></p> <p><strong>A.I. Hernandez-Serrano, X. Ding, G. Costa, </strong> G. Nurumbetov, D.M. Haddleton and <strong>E. Pickwell-MacPherson</strong> <br />Biomedical Optics Express <strong>15</strong>, 3064 (May 2024) <button class="abstractButton" onclick="location.href='https://doi.org/10.1364/BOE.513557';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Arturo2024b.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('Arturo2024b')">Show abstract</button></p> <div id="Arturo2024b" style="display: none;">Transdermal drug delivery patches are a good alternative to hypodermic drug injection. The drug delivery efficiency depends strongly on the hydration of the skin under treatment, and therefore, it is essential to study the effects on the skin induced by the application of these medical-grade patches. Terahertz (THz) spectroscopy shows great promise for non-invasive skin evaluation due to its high sensitivity to subtle changes in water content, low power and non-ionizing properties. In this work, we study the effects of transdermal drug delivery patches (three fully occlusive and three partially occlusive) applied on the upper arms of ten volunteers for a maximum period of 28&thinsp;h. Three different levels of propylene glycol (0&thinsp;%, 3&thinsp;% and 6&thinsp;%) are added to the patches as excipient. By performing multilayer analysis, we successfully retrieve the water content of the stratum corneum (SC) which is the outermost layer of skin, as well as its thickness at different times before and after applying the patches. This study demonstrates the potential of using THz sensing for non invasive skin monitoring and has wide applications for skin evaluation as well as the development of skin products.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1364/BOE.513557" data-hide-no-mentions="true"></div> <div><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1364/BOE.513557&amp;httpAccept=image%2Fjpeg&amp;apiKey=23942728d429d8cd622400c4a7485a23" border="0" /></div> THz spectroscopy MacPherson 2024 biomedical highlight Wed, 15 May 2024 06:25:00 GMT 8ac672c7928fa5310192adc08b124e6f https://doi.org/10.1021/acsphotonics.3c00918 <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=8a1785d88b8b07d6018b8ef67207070b" alt="image"></div><p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Gallop2023.jpeg?maxWidth=150" alt="mDABCO" style="margin-right: 10px;" border="0" align="right" /></p> <p><span class="accordion-tabbed__tab-mobile accordion__closed"><strong>Nathaniel P. Gallop</strong>, Dumitru Sirbu, David Walker, <strong>James Lloyd-Hughes</strong>, Pablo Docampo and <strong>Rebecca L. Milot</strong></span><br />ACS Photonics<span class="citation_volume"><b> 10</b></span><span class="cit-issue"></span><span class="cit-issue"><strong><span class="cit-volume"></span></strong><span class="cit-issue"> </span><span class="cit-pageRange">4022</span></span><span class="cit-pageRange"></span><strong><span class="citation_volume"></span><span class="cit-volume"></span></strong><span class="cit-issue"></span><span class="cit-pageRange"> </span>(October 2023) <button class="abstractButton" onclick="location.href='https://doi.org/10.1021/acsphotonics.3c00918';">web</button> <button class="abstractButton" onclick="location.href='https://pubs.acs.org/doi/epdf/10.1021/acsphotonics.3c00918';">pdf</button> <button class="abstractButton" onclick="showHide('Gallop2023')">Show abstract</button></p> <div id="Gallop2023" style="display: none;">We report on the emission of high-intensity pulsed terahertz radiation from the metal-free halide perovskite single crystal methyl-DABCO ammonium iodide (MDNI) under femtosecond illumination. The power and angular dependence of the THz output implicate optical rectification of the 800 nm pump as the mechanism of THz generation. Further characterization finds that, for certain crystal orientations, the angular dependence of THz emission is modulated by phonon resonances attributable to the motion of the methyl-DABCO moiety. At maximum, the THz emission spectrum of MDNI is free from significant phonon resonances, resulting in THz pulses with a temporal width of &lt;900 fs and a peak-to-peak electric field strength of approximately 0.8 kV cm&ndash;1─2 orders of magnitude higher than any other reported halide perovskite emitters. Our results point toward metal-free perovskites as a promising new class of THz emitters that brings to bear many of the advantages enjoyed by other halide perovskite materials. In particular, the broad tunability of optoelectronic properties and ease of fabrication of perovskite materials opens up the possibility of further optimizing the THz emission properties within this material class.</div> <div class="altmetric-embed" data-badge-popover="right" data-badge-type="2" data-doi="10.1021/acsphotonics.3c00918" data-hide-no-mentions="true"></div> THz spectroscopy Milot perovskites Lloyd-Hughes 2023 ultrafast highlight Thu, 02 Nov 2023 07:36:00 GMT 8a1785d88b8b07d6018b8ef67207070b https://dx.doi.org/10.1038/s41566-023-01242-9 <p><img src="https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/Aobo.png?maxWidth=350" alt="LED" style="margin-right: 10px;" border="0" align="right" /></p> <p>A. Ren, H. Wang, L. Dai, J. Xia, <strong>E. Butler-Caddle</strong>, J.A. Smith, ... S.A. Hindmarsh, A.M. Sanchez, <strong>J. Lloyd-Hughes</strong>, S. J Sweeney, ... and Wei Zhang<br />Nature Photonics<span class="cit-issue"><span class="cit-pageRange"></span></span><span class="cit-pageRange"></span><strong><span class="citation_volume"></span> <span class="cit-volume">17</span></strong><span class="cit-pageRange"></span><strong><span class="cit-volume"></span></strong><span class="cit-issue">, </span><span class="cit-pageRange">798&ndash;805 </span>(July 2023) <button class="abstractButton" onclick="location.href='https://doi.org/10.1038/s41566-023-01242-9';">web</button> <button class="abstractButton" onclick="location.href='https://warwick.ac.uk/fac/sci/physics/research/condensedmatt/ultrafastphotonics/publications/ren2023.pdf';">pdf</button> <button class="abstractButton" onclick="showHide('ren2023')">Show abstract</button></p> <div id="ren2023" style="display: none;">Light-emitting diodes (LEDs) are ubiquitous in modern society, with applications spanning from lighting and displays to medical diagnostics and data communications. Metal-halide perovskites are promising materials for LEDs because of their excellent optoelectronic properties and solution processability. Although research has progressed substantially in optimizing their external quantum efficiency, the modulation characteristics of perovskite LEDs remain unclear. Here we report a holistic approach for realizing fast perovskite photonic sources on silicon based on tailoring alkylammonium cations in perovskite systems. We reveal the recombination behaviour of charged species at various carrier density regimes relevant for their modulation performance. By integrating a Fabry&ndash;Pérot microcavity on silicon, we demonstrate perovskite devices with efficient light outcoupling. We achieve device modulation bandwidths of up to 42.6&thinsp;MHz and data rates above 50&thinsp;Mbps, with further analysis suggesting that the bandwidth may exceed gigahertz levels. The principles developed here will support the development of perovskite light sources for next-generation data-communication architectures. The demonstration of solution-processed perovskite emitters on silicon substrates also opens up the possibility of integration with micro-electronics platforms.</div> <div align="left"><img src="https://api.elsevier.com/content/abstract/citation-count?doi=10.1038/s41566-023-01242-9&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/s41566-023-01242-9" data-hide-no-mentions="true"></div> THz spectroscopy nanomaterials photoluminescence perovskites Lloyd-Hughes 2023 ultrafast highlight Sun, 13 Aug 2023 18:37:00 GMT 8a17841a89d4febb0189f030773a4dd7