Pro Breaking Crew Battles (YAKFILMS)
分享这个视频的人喜欢
热门视频推荐
热门日志推荐
同类视频推荐
北京千橡网景科技发展有限公司：
文网文[号··京公网安备号·甲测资字
文化部监督电子邮箱：wlwh@··
文明办网文明上网举报电话： 举报邮箱：&&&&&&&&&&&&
请输入手机号，完成注册
请输入验证码
密码必须由6-20个字符组成
下载人人客户端
品评校花校草，体验校园广场分享这个视频的人喜欢
热门视频推荐
热门日志推荐
同类视频推荐
北京千橡网景科技发展有限公司：
文网文[号··京公网安备号·甲测资字
文化部监督电子邮箱：wlwh@··
文明办网文明上网举报电话： 举报邮箱：&&&&&&&&&&&&
请输入手机号，完成注册
请输入验证码
密码必须由6-20个字符组成
下载人人客户端
品评校花校草，体验校园广场OALib Journal期刊
费用：600人民币/ 99美元
查看量下载量
Phonon Spectra of Small Colloidal II-VI Semiconductor Nanocrystals
Resonant Raman spectroscopy has been employed to explore the first- and higher-order phonon spectra of several kinds of II-VI nanocrystals (NCs), with the aim of better understanding of the nature of phonon modes and forming a unified view onto the vibrational spectrum of semiconductor NCs. Particularly, besides the previously discussed TO, SO, LO, and 2LO modes, the combinational modes of TO+LO and SO+LO can be assumed to account for the lineshape of the spectrum below 2LO band. No trace of 2TO or 2SO band was detected, what can be the result of the dominance of Fr？hlich mechanism in electron-phonon coupling in II-VI compounds. The resonant phonon Raman spectrum of NCs smaller than 2？nm is shown to be dominated by a broad feature similar to the SO mode of larger NCs or phonon density of states of a bulk crystal. The understanding of the phonon spectrum of semiconductor nanocrystals (NCs), electron-phonon coupling (EPC), dependence of the phonon spectra on the NC size, surface-bound moieties, and extended environment is of a large fundamental and application significance [1–11] due to the determinant role phonons play in the optical and electrical properties of semiconductor nanostructures [12, 13]. Though a number of in-depth studies have addressed the phonon spectra of colloidal [14–20], glass-embedded [21–23] NCs, and epitaxial nanostructures [24–26], a significant divergence of the results exists concerning both the nature of the modes and their response to such factors as size, surface conditions, properties of the hosting medium and so forth. In particular, the apparently similar Raman spectra of a wide range of compounds (e.g., II-VI, III-V, and IV) and NC morphologies (dots, rods, tetrapods, wires, and discs) have been assigned differently. Recently, attempts were made to build a general picture of the phonon spectrum of various semiconductor NCs, based on analysis of the experimental Raman data and appropriate models [14, 27, 28]. This paper further explores the first- and higher-order phonon spectra of several kinds of II-VI NCs, as well as their similarity to other compounds, with the aim of better understanding of the vibrational spectrum of small NCs. High-quality NC samples were selected for this study in order to resolve Raman features, which are usually smeared by size dispersion, structural disorder, or low signal-to-noise ratio. The NC samples studied in this work have been prepared by means of colloidal chemistry according to protocols reported elsewhere [29–32], and CdSe, CdS, and CdTe NC samples of the same mean diameter (~4？nm)
References
[]&&G. Gouadec and P. Colomban, “Raman spectroscopy of nanostructures and nanosized materials,” Journal of Raman Spectroscopy, vol. 38, no. 6, pp. 598–603, 2007.
[]&&F. García-Santamaría, S. Brovelli, R. Viswanatha et al., “Breakdown of volume scaling in auger recombination in CdSe/CdS heteronanocrystals: the role of the core-shell interface,” Nano Letters, vol. 11, no. 2, pp. 687–693, 2011.
[]&&Q. H. Zhong, “Optical phonon modes and electron-phonon interaction in a quantized CdS spherical film,” Physica B, vol. 404, no. 8–11, pp. , 2009.
[]&&P. M. Chassaing, F. Demangeot, V. Paillard et al., “Surface optical phonons as a probe of organic ligands on ZnO nanoparticles: an investigation using a dielectric continuum model and Raman spectrometry,” Physical Review B, vol. 77, no. 15, Article ID 08.
[]&&C. Chen, M. Dutta, and M. A. Stroscio, “Surface-optical phonon assisted transitions in quantum dots,” Journal of Applied Physics, vol. 96, no. 4, Article ID 2049, pp. , 2004.
[]&&S. K. Gupta, S. Sahoo, P. K. Jha, A. K. Arora, and Y. M. Azhniuk, “Observation of torsional mode in CdS1-x Sex nanoparticles in a borosilicate glass,” Journal of Applied Physics, vol. 106, no. 2, Article ID 09.
[]&&M. P. Lisitsa, M. Y. Valakh, and N. K. Konovets, “Phonons in mixed CdxZn1？xS semiconductors,” Physica Status Solidi B, vol. 34, pp. 269–278, 1969.
[]&&S. Biswas, M. Dutta, P. Snee, and M. A. Stroscio, “Phonon modes in semiconductor quantum dots,” Chinese Journal of Physics, vol. 49, no. 1, pp. 92–99, 2011.
[]&&S. Ma, R. Livingstone, B. Zhao, and J. R. Lombardi, “Enhanced raman spectroscopy of nanostructured semiconductor phonon modes,” Journal of Physical Chemistry Letters, vol. 2, no. 6, pp. 671–674, 2011.
[]&&T. T. K. Chi, G. Gouadec, P. Colomban, G. Wang, L. Mazerolles, and N. Q. Liem, “Off-resonance Raman analysis of wurtzite CdS ground to the nanoscale: structural and size-related effects,” Journal of Raman Spectroscopy, vol. 42, no. 5, pp. , 2011.
[]&&P. Kusch, H. Lange, M. Artemyev, and C. Thomsen, “Size-dependence of the anharmonicities in the vibrational potential of colloidal CdSe nanocrystals,” Solid State Communications, vol. 151, no. 1, pp. 67–70, 2011.
[]&&S. V. Kilina, D. S. Kilin, and O. V. Prezhdo, “Breaking the phonon bottleneck in PbSe and CdSe quantum dots: time-domain density functional theory of charge carrier relaxation,” ACS Nano, vol. 3, no. 1, pp. 93–99, 2009.
[]&&V. I. Klimov, “Linear and nonlinear optical spectroscopy of semiconductor nanocrystals,” in Handbook of Nanostructured Materials and Nanotechnology, H. S. Nalwa, Ed., vol. 4 of Optical Properties, pp. 473–481, Academic Press, New York, NY, USA, 2000.
[]&&M. I. Vasilevskiy and C. Trallero-Giner, “Resonant Raman scattering in spherical quantum dots: II-VI versus III-V semiconductor nanocrystals,” Physica Status Solidi (B), vol. 247, no. 6, pp. , 2010.
[]&&D. S. Liang, L. Shen, Z. B. Wang, Y. P. Cui, J. Y. Zhang, and Y. H. Ye, “Evolution of luminescence with shell's thickness in colloidal CdSe/CdS,” Chinese Physics Letters, vol. 25, no. 12, pp. , 2008.
[]&&Y. S. Park, A. Dmytruk, I. Dmitruk et al., “Aqueous phase synthesized CdSe nanoparticles with well-defined numbers of constituent atoms,” Journal of Physical Chemistry C, vol. 114, no. 44, pp. 1, 2010.
[]&&A. G. Rolo and M. I. Vasilevskiy, “Raman spectroscopy of optical phonons confined in semiconductor quantum dots and nanocrystals,” Journal of Raman Spectroscopy, vol. 38, no. 6, pp. 618–633, 2007.
[]&&H. Lange, M. Mohr, M. Artemyev, U. Woggon, T. Niermann, and C. Thomsen, “Optical phonons in colloidal CdSe nanorods,” Physica Status Solidi (B), vol. 247, no. 10, pp. , 2010.
[]&&O. E. Rayevska, G. Y. Grodzyuk, V. M. Dzhagan, et al., “Synthesis and characterization of white-emitting CdS quantum dots stabilized with polyethylenimine,” Journal of Physical Chemistry C, vol. 114, pp. 2, 2010.
[]&&V. Dzhagan, O. Rayevska, O. Stroyuk, et al., “Resonant Raman spectroscopy of confined and surface phonons in CdSe-caped CdS nanocrystals,” Physica Status Solidi C, vol. 6, no. 2, pp. , 2009.
[]&&Y. M. Azhniuk, V. V. Lopushansky, A. V. Gomonnai, V. O. Yukhymchuk, I. I. Turok, and Y. I. Studenyak, “Spectroscopic studies of thermal treatment effect on the composition and size of CdS1-xSex nanocrystals in borosilicate glass,” Journal of Physics and Chemistry of Solids, vol. 69, no. 1, pp. 139–146, 2008.
[]&&A. Ingale and K. C. Rustagi, “Raman spectra of semiconductor nanoparticles: disorder-activated phonons,” Physical Review B, vol. 58, no. 11, pp. , 1998.
[]&&A. Roy and A. K. Sood, “Surface and confined optical phonons in CdSx-Se1-x nanoparticles in a glass matrix,” Physical Review B, vol. 53, no. 18, pp. 1, 1996.
[]&&A. G. Milekhin, A. I. Toropov, A. K. Bakarov et al., “Interface phonons in InAs and AlAs quantum dot structures,” Physical Review B, vol. 70, no. 8, Article ID
pages, 2004.
[]&&A. I. Mashin, A. V. Nezhdanov, D. O. Filatov et al., “Confocal Raman microscopy of self-assembled GeSi/Si(001) Islands,” Semiconductors, vol. 44, no. 11, pp. , 2010.
[]&&A. M. Yaremko, V. O. Yukhymchuk, M. Y. Valakh et al., “Theoretical and experimental investigations of single- and multilayer structures with SiGe nanoislands,” Materials Science and Engineering C, vol. 23, no. 6–8, pp. , 2003.
[]&&C. C. Yang and S. Li, “Size-dependent raman red shifts of semiconductor nanocrystals,” Journal of Physical Chemistry B, vol. 112, no. 45, pp. 1, 2008.
[]&&V. Dzhagan, M. Y. Valakh, J. Kolny-Olesiak, et al., “Resonant Raman study of phonons in high-quality colloidal CdTe nanocrystals,” Applied Physics Letters, vol. 94, no. 24, Article ID 09.
[]&&V. Dzhagan, I. Lokteva, C. Himcinschi, et al., “Phonon Raman spectra of colloidal CdTe nanocrystals: effect of size, non-stoichiometry and ligand exchange,” Nanoscale Research Letters, vol. 6, no. 1, pp. 79–88, 2011.
[]&&A. E. Raevskaya, A. L. Stroyuk, S. Y. Kuchmii, et al., “Optical study of CdS- and ZnS-passivated CdSe nanocrystals in gelatin films,” Journal of Physics, vol. 19, no. 38, Article ID 07.
[]&&V. M. Dzhagan, M. Y. Valakh, A. E. Raevskaya, et al., “Size effects on Raman spectra of small CdSe nanocrystals in polymer films,” Nanotechnology, vol. 19, Article ID 07.
[]&&V. M. Dzhagan, I. Lokteva, M. Y. Valakh, et al., “Spectral features above LO phonon frequency in resonant Raman scattering spectra of small CdSe nanocrystals,” Journal of Applied Physics, vol. 106, Article ID 09.
[]&&H. Richter, Z. P. Wang, and L. Ley, “The one phonon Raman spectrum in microcrystalline silicon,” Solid State Communications, vol. 39, no. 5, pp. 625–629, 1981.
[]&&A. G. Rolo, M. I. Vasilevskiy, M. Hamma, and C. Trallero-Giner, “Anomalous first-order Raman scattering in III-V quantum dots: optical deformation potential interaction,” Physical Review B, vol. 78, no. 8, Article ID 08.
[]&&M. P. Chamberlain, C. Trallero-Giner, and M. Cardona, “Theory of one-phonon Raman scattering in semiconductor microcrystallites,” Physical Review B, vol. 51, no. 3, pp. , 1995.
[]&&L. Lu, X. L. Xu, W. T. Liang, and H. F. Lu, “Raman analysis of CdSe/CdS core-shell quantum dots with different CdS shell thickness,” Journal of Physics Condensed Matter, vol. 19, no. 40, Article ID 07.
[]&&D. Nesheva, Z. Aneva, M. J. ？？epanovi？ et al., “Composition and structure of ZnxCd1-xSe single layers prepared by thermal evaporation of ZnSe and CdSe,” Journal of Physics: Conference Series, vol. 253, no. 1, 2010.
[]&&C. Chen, M. Dutta, and M. A. Stroscio, “Surface-optical phonon assisted transitions in quantum dots,” Journal of Applied Physics, vol. 96, no. 4, Article ID 2049, pp. , 2004.
[]&&S. Hayashi and R. Ruppin, “Raman scattering from GaP microcrystals: analysis of the surface phonon peak,” Journal of Physics C, vol. 18, no. 12, Article ID .
[]&&V. M. Dzhagan, M. Y. Valakh, O. E. Raevska, et al., “The influence of shell parameters on phonons in core–shell nanocrystals: a resonant Raman study,” Nanotechnology, vol. 20, Article ID 09.
[]&&M. Mohr and C. Thomsen, “Phonons in bulk CdSe and CdSe nanowires,” Nanotechnology, vol. 20, no. 11, Article ID 09.
[]&&S. Xu, C. Wang, and Y. Cui, “Theoretical investigation of CdSe clusters: influence of solvent and ligand on nanocrystals,” Journal of Molecular Modeling, vol. 16, no. 3, pp. 469–473, 2010.
[]&&A. G. Rolo, M. I. Vasilevskiy, N. P. Gaponik, A. L. Rogach, and M. J. M. Gomes, “Confined optical vibrations in CdTe quantum dots and clusters,” Physica Status Solidi (B), vol. 229, no. 1, pp. 433–437, 2002.
Please enable JavaScript to view the
&&&OALib Suggest
Live SupportAsk us anythingBboy LILOU Tutorial Part 1 of 4
YAK FILMS BREAK DANCING in Paris, France_土豆_高清视频在线观看King Bones Bonebreaking Tutorial Part 1-4 Full Version- YAK FILMS_土豆_高清视频在线观看