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Local anisotropy and giant enhancement of local electromagnetic fields in fractal aggregates of metal nanoparticles / S. V. Karpov [et al.]> // Phys. Rev. B. - 2005. - Vol. 72, Is. 20. - Ст. 205425, DOI 10.1103/PhysRevB.72.205425. - Cited References: 56
. - ISSN 1098-0121РУБ Physics, Condensed Matter Рубрики: SMALL-PARTICLE COMPOSITES DIFFUSION-LIMITED AGGREGATION OPTICAL-PROPERTIES SELECTIVE PHOTOMODIFICATION NUMERICAL-SIMULATION DISORDERED CLUSTERS ABSORPTION-SPECTRUM PARTICULATE MATTER NONLINEAR OPTICS LIGHT-SCATTERING Аннотация: We have shown within quasistatic approximation that the giant fluctuations of a local electromagnetic field in random fractal aggregates of silver nanospheres are strongly correlated with a local anisotropy factor S which is defined in this paper. The latter is a purely geometrical parameter which characterizes the deviation of local environment of a given nanosphere in an aggregate from spherical symmetry. Therefore, it is possible to predict the sites with anomalously large local fields in an aggregate without explicitly solving the electromagnetic problem. We have also demonstrated that the average (over nanospheres) value of S does not depend noticeably on the fractal dimension D, except when D approaches the trivial limit D=3. In this case, as one can expect, the average local environment becomes spherically symmetrical and S approaches zero. This corresponds to the well-known fact that in trivial aggregates, fluctuations of local electromagnetic fields are much weaker than in fractal aggregates. Thus, we find that, within the quasistatics, the large-scale geometry does not have a significant impact on local electromagnetic responses in nanoaggregates in a wide range of fractal dimensions. However, this prediction is expected not to be correct in aggregates which are sufficiently large for the intermediate- and radiation-zone interaction of individual nanospheres to become important.
WOS, Scopus, Читать в сети ИФ Держатели документа: Russian Acad Sci, LV Kirensky Phys Inst, Siberian Branch, Krasnoyarsk 660036, Russia Krasnoyarsk State Tech Univ, Dept Phys & Engn, Krasnoyarsk 660028, Russia Univ Penn, Dept Radiol, Philadelphia, PA 19104 USA Univ Penn, Dept Bioengn, Philadelphia, PA 19104 USA ИФ СО РАН L. V. Kirensky Institute of Physics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk 660036, Russian Federation Department of Physics and Engineering, Krasnoyarsk State Technical University, Krasnoyarsk 660028, Russian Federation Departments of Radiology and Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, United States Доп.точки доступа: Karpov, S. V.; Карпов, Сергей Васильевич; Gerasimov, V. S.; Герасимов, Валерий Сергеевич; Isaev, I. L.; Исаев, Иван Леонидович; Markel, V. A. } Найти похожие
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