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S ; 119081 119083 99 ; S ; S ; S ; Copyright (2011) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. We perform Raman-scattering measurements at high hydrostatic pressures on c-face and a-face InN layers to investigate the high-pressure behavior of the zone-center optical phonons of wurtzite InN. Linear pressure coefficients and mode Grneisen parameters are obtained, and the experimental results are compared with theoretical values obtained from ab initio lattice-dynamical calculations. Good agreement is found between the experimental and calculated results. © 2011 American Institute of Physics. Work supported by the Spanish MICINN (Projects MAT2010-16116, MAT2008-06873-C02-02, MAT2010-21270-C04-04, and CSD2007-00045), the Catalan Government (BE-DG 2009), and the Spanish Council for Research (PIE2009-CSIC). Ibanez, J.; Manjón Herrera, FJ.; Segura, A.; Oliva, R.; Cusco, R.; Vilaplana Cerda, RI.; Yamaguchi, T. (2011). High-pressure Raman scattering in wurtzite indium nitride. Applied Physics Letters. 99:119081-119083. https://doi.org/10.1063/1.3609327 Veal, T., McConville, C., & Schaff, W. (Eds.). (2009). Indium Nitride and Related Alloys. doi:10.1201/9781420078107 Gallinat, C. S., Koblmüller, G., Brown, J. S., Bernardis, S., Speck, J. S., Chern, G. D., … Wraback, M. (2006). In-polar InN grown by plasma-assisted molecular beam epitaxy. Applied Physics Letters, 89(3), 032109. doi:10.1063/1.2234274 Li, S. X., Wu, J., Haller, E. E., Walukiewicz, W., Shan, W., Lu, H., & Schaff, W. J. (2003). Hydrostatic pressure dependence of the fundamental bandgap of InN and In-rich group III nitride alloys. Applied Physics Letters, 83(24), 4963-4965. doi:10.1063/1.1633681 Gorczyca, I., Plesiewicz, J., Dmowski, L., Suski, T., Christensen, N. E., Svane, A., … Speck, J. S. (2008). Electronic structure and effective masses of InN under pressure. Journal of Applied Physics, 104(1), 013704. ...

Copyright (2011) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. ; We perform Raman-scattering measurements at high hydrostatic pressures on c-face and a-face InN layers to investigate the high-pressure behavior of the zone-center optical phonons of wurtzite InN. Linear pressure coefficients and mode Grneisen parameters are obtained, and the experimental results are compared with theoretical values obtained from ab initio lattice-dynamical calculations. Good agreement is found between the experimental and calculated results. © 2011 American Institute of Physics. ; Work supported by the Spanish MICINN (Projects MAT2010-16116, MAT2008-06873-C02-02, MAT2010-21270-C04-04, and CSD2007-00045), the Catalan Government (BE-DG 2009), and the Spanish Council for Research (PIE2009-CSIC). ; Ibanez, J.; Manjón Herrera, FJ.; Segura, A.; Oliva, R.; Cusco, R.; Vilaplana Cerda, RI.; Yamaguchi, T. (2011). High-pressure Raman scattering in wurtzite indium nitride. Applied Physics Letters. 99:119081-119083. https://doi.org/10.1063/1.3609327 ; S ; 119081 ; 119083 ; 99 ; Veal, T., McConville, C., & Schaff, W. (Eds.). (2009). Indium Nitride and Related Alloys. doi:10.1201/9781420078107 ; Gallinat, C. S., Koblmüller, G., Brown, J. S., Bernardis, S., Speck, J. S., Chern, G. D., … Wraback, M. (2006). In-polar InN grown by plasma-assisted molecular beam epitaxy. Applied Physics Letters, 89(3), 032109. doi:10.1063/1.2234274 ; Li, S. X., Wu, J., Haller, E. E., Walukiewicz, W., Shan, W., Lu, H., & Schaff, W. J. (2003). Hydrostatic pressure dependence of the fundamental bandgap of InN and In-rich group III nitride alloys. Applied Physics Letters, 83(24), 4963-4965. doi:10.1063/1.1633681 ; Gorczyca, I., Plesiewicz, J., Dmowski, L., Suski, T., Christensen, N. E., Svane, A., … Speck, J. S. (2008). Electronic structure and effective masses of InN under pressure. Journal of Applied Physics, 104(1), 013704. ...

Anisotropic metallic nanoparticles (NPs) have unique optical properties, which lend them to applications such as surface-enhanced Raman scattering (SERS) spectroscopy. Star-shaped gold (Au) NPs were prepared in aqueous solutions by the seed-mediated growth method and tested for Raman enhancement using 2-mercaptopyridine (2-MPy) and crystal violet (CV) probing molecules. For both molecules, the SERS activity of the nanostars was notably stronger than that of the spherical Au NPs of similar size. The Raman enhancement factors (EFs) for 2-MPy on Au nanostars and nanorods are comparable and estimated as greater than 5 orders of magnitude. However, the enhancement for CV on nanostars was significantly higher than for nanorods, in particular at CV concentrations of 100 nm or lower. This article is a US Government work and is in the public domain in the USA. Published in 2008 by John Wiley & Sons, Ltd.

The discovery of the enhancement of Raman scattering by molecules adsorbed on nanostructured metal surfaces is a landmark in the history of spectroscopic and analytical techniques. Significant experimental and theoretical effort has been directed toward understanding the surface-enhanced Raman scattering (SERS) effect and demonstrating its potential in various types of ultrasensitive sensing applications in a wide variety of fields. In the 45 years since its discovery, SERS has blossomed into a rich area of research and technology, but additional efforts are still needed before it can be routinely used analytically and in commercial products. In this Review, prominent authors from around the world joined together to summarize the state of the art in understanding and using SERS and to predict what can be expected in the near future in terms of research, applications, and technological development. This Review is dedicated to SERS pioneer and our coauthor, the late Prof. Richard Van Duyne, whom we lost during the preparation of this article. ; Funding is acknowledged from the European Research Council (ERC Advanced Grant No. 787510-4DBIOSERS to L.M.L.-M., ERC Advanced Grant No. 789104-eNANO to F.J.G.A., ERC Starting Grant No. 259432-MULTIBIOPHOT to J.K., ERC Consolidator Grant No. 772108-DarkSERS); the Department of Education of the Basque Government (Grant No. IT1164-19 to J.A.); the Spanish MINECO (CTQ2017-88648-R to R.A.-P., MAT2016-77809-R to I.P.-S. and J.P.-J.); the EPSRC (EP/P034063/1 to S.B., EP/L027151/1 to J.B., EP/L014165/1 to D.G. and K.F.); IDUN-Danish National Research Foundation (DNRF122) and Villum Fonden (Grant No. 9301) to A.B.; the National Research Foundation of Korea (Grant No. 2019R1A2C3004375 to J.B.); the German Science Foundation, DFG (SFB 1278 Polytarget (Project B4) to V.D., Grant No. SCHL 594/13-1 to S.S., Germany's Excellence Strategy (EXC 2089/1-390776260) to S.M.); the Federal Ministry of Education and Research, Germany (BMBF) (Grant InfectoGnostics 13GW0096F to D.C.-M. and J.P.); DARPA-16-35-INTERCEPT-FP-018 to L.F.; the UK BBSRC (Grant No. BB/L014823/1 to R.G.); the Department of Science and Technology (DST Nanomission Project SR/NM/NS-23/2016 to K.G.T.); the U.S. National Science Foundation (Grant No. CHE-1707859 to A.J.H., Center for Sustainable Nanotechnology CHE-1503408 (Centers for Chemical Innovation Program) to C.L.H., Center for Chemical Innovation Chemistry at the Space-Time Limit (CaSTL) CHE-1414466 to G.C.S. and R.P.V.D., Grant No. CHE-1807269 to K.A.W.); the Knut and Alice Wallenberg Foundation to M.K.; the Office of Naval Research (Grant No. N00014-18-1-2876 to N.A.K.); Royal Society of New Zealand Te Apa̅rangi to E.L.R. and B.A.; Singapore Ministry of Education, Tier 1 (RG11/18) to X.Y.L.; the Photoexcitonix Project in Hokkaido Univ., Japan, to K.M.; BioNano Health-Guard Research Center funded by the Ministry of Science and ICT (MSIT) of Korea as Global Frontier Project (Grant No. H-GUARD_2013M3A6B2078947) to J.-M.N.; NSFC of P. R. China (Grant No. 21705015 to Y.O., Grant No. 21633005 to B.R.); National Key R&D Program (2017YFA0206902) to C.X. This work was coordinated under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency—Grant No. MDM-2017-0720. ; Peer reviewed

The photoluminescence (PL) of ZnO-opal structures excited by a 351.1 nm laser line was studied. The fabrication of these structures was done by infiltration of ZnO from an aqueous solution of zinc nitrate into opal matrices. It was observed that the emission spectrum of thick ZnO layers grown on the surface of bulk opals exhibited narrow PL bands associated with the recombination of bound and free-excitons. The results showed that the strong exciton-LO phonon and exciton-Frohlich mode coupling in ZnO nanostructures was deduced from the analysis of multiphonon excitonic resonant Raman scattering. ; This work was supported by INTAS under Grant No. 01-0796. ISSP authors are grateful for the financial support received from the Russian Foundation for Basic Research (Project No. 01-02-97024) and from the Russian Federation Government under Contract No. 40.012.1.1.11.54. ; Peer Reviewed

arXiv:1509.03851v3 ; Plasmon-enhanced Raman scattering can push single-molecule vibrational spectroscopy beyond a regime addressable by classical electrodynamics. We employ a quantum electrodynamics (QED) description of the coherent interaction of plasmons and molecular vibrations that reveal the emergence of nonlinearities in the inelastic response of the system. For realistic situations, we predict the onset of phonon-stimulated Raman scattering and a counterintuitive dependence of the anti-Stokes emission on the frequency of excitation. We further show that this QED framework opens a venue to analyze the correlations of photons emitted from a plasmonic cavity. ; M.K.S., R.E., and J.A. acknowledge funding from the project FIS2013-41184-P of the Spanish Ministry of Economy and Competitiveness, the ETORTEK IE14-393 NANOGUNE'14 project of the Department of Industry of the Government of the Basque Country, project IT756-13 of the Department of Education and Culture of the Basque Country, scholarship AP-2012-4204 from the Spanish Ministry of Education, Culture and Sport, financial assistance award 70NANB15H32 from U.S. Department of Commerce, National Institute of Standards and Technology, and the Fellows Gipuzkoa program of the Gipuzkoako Foru Aldundia through the FEDER funding scheme of the European Union, Una manera de hacer Europa. A.G.T. acknowledges support from the IntraEuropean Fellowship NanoQuIS (625955). ; Peer reviewed

In this work, the intermolecular interactions of diacetyl and water molecules were studied using the vibration spectrum. The Raman scattering spectra obtained in the range of 500– 2000 cm−1 were analyzed and compared with the results of calculations. For the first time аlso, the charge density distribution and 3D potential energy graphs are examined using simulations for diacetyl molecules. With the increase in the number of molecules at the formation of molecular clusters with the water molecule, the saturation of the intermolecular interaction energy corresponding to a single Н-bond is observed. This corresponds to DA+(Н2O)3 molecular clusters and allows one to conclude that this cluster is stable relative to the others.

High-pressure Raman scattering measurements have been carried out in ZnGa2Se4 for both tetragonal defect chalcopyrite and defect stannite structures. Experimental results have been compared with theoretical lattice dynamics ab initio calculations and confirm that both phases exhibit different Raman-active phonons with slightly different pressure dependence. A pressure-induced phase transition to a Raman-inactive phase occurs for both phases; however, the sample with defect chalcopyrite structure requires slightly higher pressures than the sample with defect stannite structure to fully transform into the Raman-inactive phase. On downstroke, the Raman-inactive phase transforms into a phase that could be attributed to a disordered zincblende structure for both original phases; however, the sample with original defect chalcopyrite structure compressed just above 20¿GPa, where the transformation to the Raman-inactive phase is not completed, returns on downstroke mainly to its original structure but shows a new peak that does not correspond to the defect chalcopyrite phase. The pressure dependence of the Raman spectra with this new peak and those of the disordered zincblende phase is also reported and discussed. © 2013 AIP Publishing LLC ; This study was supported by the Spanish government MEC under Grants No. MAT2010-21270-C04-01/03/04, by MALTA Consolider Ingenio 2010 project (CSD2007-00045), and by the Vicerrectorado de Investigacion y Desarrollo of the Universitat Politecnica de Valencia (UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11). E.P.-G., A.M., and P.R.-H. acknowledge computing time provided by Red Espanola de Supercomputacion (RES) and MALTA-Cluster. ; Vilaplana Cerda, RI.; Gomis Hilario, O.; Pérez-González, E.; Ortiz, HM.; Manjón Herrera, FJ.; Rodríguez-Hernández, P.; Muñoz, A. (2013). High-pressure Raman scattering study of defect chalcopyrite and defect stannite ZnGa2Se4. Journal of Applied Physics. 113:2335011-23350110. https://doi.org/10.1063/1.4810854 ; S ; 2335011 ; 23350110 ; 113 ; A. ...

This project aims to fabricate nanostructures (AgNPS) using the electrical exploding wire (EEW) technique using Rhodamine 6G dye as the probe molecule, investigate the effect of AgNPS on the absorption spectra and surface-enhanced Raman scattering (SERS) activities, and advance using porous silicon as an active substrate for surface-enhanced Raman scattering (SERS). X-Ray diffraction (XRD) was used to investigate the structural properties of the nanostructures (AgNPs). Field emission scanning electron microscopy (FE-SEM) was used to investigate surface morphology. A double beam UV-Vis Spectrophotometer was used to analyze the mixed R6G laser dye(of concentration 1x M) absorption spectra with the nanostructures AgNPS (of concentration 24x M). A sunshine Raman microscope device (the objective lens used was (50x)). was used to analyze R6G combined with nanostructures Raman spectra. All samples have shown SERS activity that increased with increasing the hot spots. The SERS enhancement factor for R6G dye(of 1x10-6 M concentration) when mixed with (AgNPS) nanostructures has reached to(2.48 x 106) and the lowest detection limit reached to (1 x 10-14 M) at the wave number (1652 cm-1) using excited laser source (λexc. = 532nm)

Under the terms of the Creative Commons Attribution 3.0 Unported License.-- Trabajo presentado a la 49th European High Pressure Research Group Conference (EHPRG), celebrada en Mumbai (India) del 25 al 30 de septiembre de 2011.-- et al. ; High-pressure Raman scattering measurements have been carried out in ZnGa2Se4 for both tetragonal defect chalcopyrite and defect stannite structures. Experimental results have been compared with theoretical lattice dynamics ab initio calculations and confirm that both phases exhibit different Raman-active phonons with slightly different pressure dependence. A pressure-induced phase transition to a Raman-inactive phase occurs for both phases; however, the sample with defect chalcopyrite structure requires slightly higher pressures than the sample with defect stannite structure to fully transform into the Raman-inactive phase. On downstroke, the Raman-inactive phase transforms into a phase that could be attributed to a disordered zincblende structure for both original phases; however, the sample with original defect chalcopyrite structure compressed just above 20 GPa, where the transformation to the Raman-inactive phase is not completed, returns on downstroke mainly to its original structure but shows a new peak that does not correspond to the defect chalcopyrite phase. The pressure dependence of the Raman spectra with this new peak and those of the disordered zincblende phase is also reported and discussed. © 2013 AIP Publishing LLC. ; This study was supported by the Spanish government MEC under Grants No. MAT2010-21270-C04-01/03/04, by MALTA Consolider Ingenio 2010 project (CSD2007- 00045), and by the Vicerrectorado de Investigación y Desarrollo of the Universitat Politécnica de Valencia (UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11). ; Peer Reviewed