المؤلفون: Caligiuri, Vincenzo, Kwon, Hyunah, Griesi, Andrea, Ivanov, Yurii P., Schirato, Andrea, Alabastri, Alessandro, Cuscunà, Massimo, Balestra, Gianluca, De Luca, Antonio, Tapani, Tlek, Lin, Haifeng, Maccaferri, Nicolò, Dr., 1988, Krahne, Roman, Divitini, Giorgio, Fischer, Peer, Garoli, Denis

المصدر: Nanophotonics. 13(7):1159-1167

مصطلحات موضوعية: catholuminescence, EELS, multilayer, nanoporous metal, plasmonics

الوصف: Nanoporous metals are a class of nanostructured materials finding extensive applications in multiple fields thanks to their unique properties attributed to their high surface area and interconnected nanoscale ligaments. They can be prepared following different strategies, but the deposition of an arbitrary pure porous metal is still challenging. Recently, a dry synthesis of nanoporous films based on the plasma treatment of metal thin layers deposited by physical vapour deposition has been demonstrated, as a general route to form pure nanoporous films from a large set of metals. An interesting aspect related to this approach is the possibility to apply the same methodology to deposit the porous films as a multilayer. In this way, it is possible to explore the properties of different porous metals in close contact. As demonstrated in this paper, interesting plasmonic properties emerge in a nanoporous Au–Ag bi-layer. The versatility of the method coupled with the possibility to include many different metals, provides an opportunity to tailor their optical resonances and to exploit the chemical and mechanical properties of components, which is of great interest to applications ranging from sensing, to photochemistry and photocatalysis.

وصف الملف: electronic

الوصول الحر: https://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-222964Test
https://doi.org/10.1515/nanoph-2023-0942Test
https://umu.diva-portal.org/smash/get/diva2:1850941/FULLTEXT01.pdfTest

المؤلفون: Caligiuri, Vincenzo, Kwon, Hyunah, Griesi, Andrea, Ivanov, Yurii P., Schirato, Andrea, Alabastri, Alessandro, Cuscunà, Massimo, Balestra, Gianluca, De Luca, Antonio, Tapani, Tlek, Lin, Haifeng, Maccaferri, Nicolo, Krahne, Roman, Divitini, Giorgio, Fischer, Peer, Garoli, Denis

مصطلحات موضوعية: Physics - Applied Physics

الوصف: Nanoporous metals are a class of nanostructured materials finding extensive applications in multiple fields thanks to their unique properties attributed to their high surface area and interconnected nanoscale ligaments. They can be pre-pared following different strategies, but the deposition of an arbitrary pure porous metal is still challenging. Recently, a dry synthesis of nanoporous films based on the plasma treat-ment of metal thin layers deposited by physical vapour deposition has been demonstrated, as a general route to form pure nanoporous films from a large set of metals. An interest-ing aspect related to this approach is the possibility to apply the same methodology to deposit the porous films as a multilayer. In this way, it is possible to explore the properties of different porous metals in close contact. As demonstrated in this paper, interesting plasmonic properties emerge in a nanoporous Au-Ag bi-layer. The versatility of the method coupled with the possibility to include many different metals, provides an opportunity to tailor their optical resonances and to exploit the chemical and mechanical properties of compo-nents, which is of great interest to applications ranging from sensing, to photochemistry and photocatalysis.

الوصول الحر: http://arxiv.org/abs/2312.15438Test

المؤلفون: Koya, Alemayehu Nana, Zhu, Xiangchao, Ohannesian, Nareg, Yanik, A. Ali, Alabastri, Alessandro, Zaccaria, Remo Proietti, Krahne, Roman, Shih, Wei-Chuan, Garoli, Denis

مصطلحات موضوعية: Physics - Applied Physics, Physics - Optics

الوصف: The field of plasmonics is capable of enabling interesting applications in the different wavelength ranges, spanning from the ultraviolet up to the infrared. The choice of plasmonic material and how the material is nanostructured have significant implications for ultimate performance of any plasmonic device. Artificially designed nanoporous metals have interesting material properties including large specific surface area, distinctive optical properties, high electrical conductivity, and reduced stiffness, implying their potentials for many applications. This manuscript reviews the wide range of available nanoporous metals, mainly focusing on their properties as plasmonic materials. While extensive reports on the use and characterization of NPMs exist, a detailed discussion on their connection with surface plasmons and enhanced spectroscopies as well as photocatalysis is missing. Here, we report on different metals investigated, from the most used nanoporous gold to mixed metal compounds, and discuss each of these plasmonic materials suitability for a range of structural design and applications. Finally, we discuss the potentials and limitations of the traditional and alternative plasmonic materials for applications in enhanced spectroscopy and photocatalysis.

الوصول الحر: http://arxiv.org/abs/2312.02609Test

المؤلفون: Tay, Fuyang, Mojibpour, Ali, Sanders, Stephen, Liang, Shuang, Xu, Hongjing, Gardner, Geoff C., Baydin, Andrey, Manfra, Michael J., Alabastri, Alessandro, Hagenmüller, David, Kono, Junichiro

مصطلحات موضوعية: Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Optics

الوصف: Recent theoretical studies have highlighted the role of spatially varying cavity electromagnetic fields in exploring novel cavity quantum electrodynamics (cQED) phenomena, such as the potential realization of the elusive Dicke superradiant phase transition. One-dimensional photonic-crystal cavities (PCCs), widely used for studying solid-state cQED systems, have uniform spatial profiles in the lateral plane. Three-dimensional (3D) PCCs, which exhibit discrete in-plane translational symmetry, overcome this limitation, but fabrication challenges have hindered the achievement of strong coupling in 3D-PCCs. Here, we report the realization of multimode ultrastrong coupling in a 3D-PCC at terahertz frequencies. The multimode coupling between the 3D-PCC's cavity modes and the cyclotron resonance of a Landau-quantized two-dimensional electron gas in GaAs is significantly influenced by the spatial profiles of the cavity modes, leading to distinct coupling scenarios depending on the probe polarization. Our experimental results are in excellent agreement with a multimode extended Hopfield model that accounts for the spatial inhomogeneity of the cavity field. Guided by the model, we discuss the possible strong ground-state correlations between different cavity modes and introduce relevant figures of merit for the multimode ultrastrong coupling regime. Our findings emphasize the importance of spatially nonuniform cavity mode profiles in probing nonintuitive quantum phenomena expected for the ground states of cQED systems in the ultrastrong coupling regime.
Comment: 36 pages, 13 figures

الوصول الحر: http://arxiv.org/abs/2308.12427Test

المؤلفون: Liao, Shusen, Zhu, Yunxuan, Ye, Qian, Sanders, Stephen, Yang, Jiawei, Alabastri, Alessandro, Natelson, Douglas

المصدر: J. Phys. Chem. Lett. 14, 7574-7580 (2023)

مصطلحات موضوعية: Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Optics

الوصف: Surface-enhanced Raman spectroscopy (SERS) is enabled by local surface plasmon resonances (LSPRs) in metallic nanogaps. When SERS is excited by direct illumination of the nanogap, the background heating of lattice and electrons can prevent further manipulation of the molecules. To overcome this issue, we report SERS in electromigrated gold molecular junctions excited remotely: surface plasmon polaritons (SPPs) are excited at nearby gratings, propagate to the junction, and couple to the local nanogap plasmon modes. Like direct excitation, remote excitation of the nanogap can generate both SERS emission and an open-circuit photovoltage (OCPV). We compare SERS intensity and OCPV in both direct and remote illumination configurations. SERS spectra obtained by remote excitation are much more stable than those obtained through direct excitation when photon count rates are comparable. By statistical analysis of 33 devices, coupling efficiency of remote excitation is calculated to be around 10%, consistent with the simulated energy flow.
Comment: 20 pages, 4 figures, plus 19 pages, 11 figures supporting information

الوصول الحر: http://arxiv.org/abs/2308.11547Test

المؤلفون: Malerba, Mario, Sotgiu, Simone, Schirato, Andrea, Baldassarre, Leonetta, Gillibert, Raymond, Giliberti, Valeria, Jeannin, Mathieu, Manceau, Jean-Michel, Li, Lianhe, Davies, Alexander Giles, Linfield, Edmund H., Alabastri, Alessandro, Ortolani, Michele, Colombelli, Raffaele

مصطلحات موضوعية: Physics - Optics, Condensed Matter - Mesoscale and Nanoscale Physics

الوصف: Recently, the concept of strong light-matter coupling has been demonstrated in semiconductor structures, and it is poised to revolutionize the design and implementation of components, including solid state lasers and detectors. We demonstrate an original nanospectroscopy technique that permits to study the light-matter interaction in single subwavelength-sized nano-cavities where far-field spectroscopy is not possible using conventional techniques. We inserted a thin ($\approx$ 150 nm) polymer layer with negligible absorption in the mid-IR (5 $\mu$m < $\lambda$ < 12 $\mu$m) inside a metal-insulator-metal resonant cavity, where a photonic mode and the intersubband transition of a semiconductor quantum well are strongly coupled. The intersubband transition peaks at $\lambda$ = 8.3 $\mu$m, and the nano-cavity is overall 270 nm thick. Acting as a non-perturbative transducer, the polymer layer introduces only a limited alteration of the optical response while allowing to reveal the optical power absorbed inside the concealed cavity. Spectroscopy of the cavity losses is enabled by the polymer thermal expansion due to heat dissipation in the active part of the cavity, and performed using an atomic force microscope (AFM). This innovative approach allows the typical anticrossing characteristic of the polaritonic dispersion to be identified in the cavity loss spectra at the single nano-resonator level. Results also suggest that near-field coupling of the external drive field to the top metal patch mediated by a metal-coated AFM probe tip is possible, and it enables the near-field mapping of the cavity mode symmetry including in the presence of strong light-matter interaction.

الوصول الحر: http://arxiv.org/abs/2211.14911Test

المؤلفون: Vincenzo Caligiuri, Hyunah Kwon, Andrea Griesi, Yurii P. Ivanov, Andrea Schirato, Alessandro Alabastri, Massimo Cuscunà, Gianluca Balestra, Antonio De Luca, Tlek Tapani, Haifeng Lin, Nicolò Maccaferri, Roman Krahne, Giorgio Divitini, Peer Fischer, Denis Garoli

المساهمون: Caligiuri, Vincenzo, Kwon, Hyunah, Griesi, Andrea, Ivanov, Yurii P., Schirato, Andrea, Alabastri, Alessandro, Cuscunà, Massimo, Balestra, Gianluca, De Luca, Antonio, Tapani, Tlek, Lin, Haifeng, Maccaferri, Nicolò, Krahne, Roman, Divitini, Giorgio, Fischer, Peer, Garoli, Denis

العلاقة: firstpage:1; lastpage:9; journal:NANOPHOTONICS; https://hdl.handle.net/11380/1334426Test

الإتاحة: https://doi.org/10.1515/nanoph-2023-0942Test
https://hdl.handle.net/11380/1334426Test

المؤلفون: Schirato, Andrea, Toma, Andrea, Zaccaria, Remo Proietti, Alabastri, Alessandro, Cerullo, Giulio, Della Valle, Giuseppe, Maiuri, Margherita

مصطلحات موضوعية: Physics - Optics

الوصف: Optical metasurfaces have come into the spotlight as a promising platform for light manipulation at the nanoscale, including ultrafast all-optical control via excitation with femtosecond laser pulses. Recently, dichroic metasurfaces have been exploited to modulate the polarization state of light with unprecedented speed. Here, we theoretically predict and experimentally demonstrate by pump-probe spectroscopy the capability to reconfigure the ultrafast dichroic signal of a gold metasurface by simply acting on the polarization of the pump pulse, which is shown to reshape the spatio-temporal distribution of the optical perturbation. The photoinduced anisotropic response, driven by out-of-equilibrium carriers and extinguished in a sub-picosecond temporal window, is readily controlled in intensity by tuning the polarization direction of the excitation up to a full sign reversal. This work proves that nonlinear metasurfaces offer the flexibility to tailor their ultrafast optical response in a fully all-optically reconfigurable platform.

الوصول الحر: http://arxiv.org/abs/2201.03183Test

المؤلفون: Cortés, Emiliano, Besteiro, Lucas V., Alabastri, Alessandro, Baldi, Andrea, Tagliabue, Giulia, Demetriadou, Angela, Narang, Prineha

المصدر: ACS Nano 14 (2020) 16202-16219

مصطلحات موضوعية: Physics - Optics

الوصف: The use of nanoplasmonics to control light and heat close to the thermodynamic limit enables exciting opportunities in the field of plasmonic catalysis. The decay of plasmonic excitations creates highly nonequilibrium distributions of hot carriers that can initiate or catalyze reactions through both thermal and nonthermal pathways. In this Perspective, we present the current understanding in the field of plasmonic catalysis, capturing vibrant debates in the literature, and discuss future avenues of exploration to overcome critical bottlenecks. Our Perspective spans first-principles theory and computation of correlated and far-from-equilibrium light-matter interactions, synthesis of new nanoplasmonic hybrids, and new steady-state and ultrafast spectroscopic probes of interactions in plasmonic catalysis, recognizing the key contributions of each discipline in realizing the promise of plasmonic catalysis. We conclude with our vision for fundamental and technological advances in the field of plasmon-driven chemical reactions in the coming years.

الوصول الحر: http://arxiv.org/abs/2108.11187Test

المؤلفون: Gharib, Mustafa, Yates, A. J., Sanders, Stephen, Gebauer, Johannes, Graf, Sebastian, Ziefuß, Anna Rosa, Nonappa, Kassier, Günther, Rehbock, Christoph, Barcikowski, Stephan, Weller, Horst, Alabastri, Alessandro, Nordlander, Peter, Parak, Wolfgang J., Chakraborty, Indranath

المساهمون: Tampere University, Materials Science and Environmental Engineering

مصطلحات موضوعية: 216 Materials engineering

الوصف: Among various hybrid nanomaterials, the combination of plasmonic nanoparticles and fluorophores in a single multifunctional nanoplatform, so-called plasmophores, has attracted significant attention in different fields such as dark field, fluorescence, and photoacoustic imaging, biosensing, photothermal, and photodynamic therapy. Herein, author report a facile and controlled synthesis route of hybrid nanoplatforms composed of fluorescent gold nanoclusters (GNCs) coupled to plasmonic gold nanorods (GNRs) using controlled silica (SiO2) dielectric spacers of different thicknesses from now on referred to as GNR@SiO2@GNC plasmophores. The results show different degrees of plasmon-enhanced fluorescence of the GNCs in their plasmophore hybrid system when placed at different distances from the plasmonic cores of the GNRs. On the other hand, these plasmophores show enhanced thermal stability compared to GNRs@CTAB (CTAB, cetyl trimethyl ammonium bromide). This results also demonstrated that upon annealing at elevated temperatures (800–1000 °C), the GNRs in the plasmophores are more thermally stable and robust than the GNRs@CTAB. More surprisingly, despite the commonly reported very low melting temperature of smaller-size nanocrystals, the GNCs in the plasmophores showed high thermal stability and do not exhibit significant structural changes at elevated temperatures (800–1000 °C). ; Peer reviewed

وصف الملف: fulltext

العلاقة: Advanced Optical Materials; ORCID: /0000-0002-6804-4128/work/155371892; https://trepo.tuni.fi/handle/10024/155537Test; URN:NBN:fi:tuni-202403132844

الإتاحة: https://doi.org/10.1002/adom.202302833Test
https://trepo.tuni.fi/handle/10024/155537Test