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Full-Text Articles in Physics
Nanoparticle Aggregation And Relaxation Effects In Ferrofluids: Studied Through Anisotropic Light Scattering, Corneliu Rablau, Prem Vaishnava, Sudakar Chandran, Ronald Tackett, Gavin Lawes, Ratna Naik
Nanoparticle Aggregation And Relaxation Effects In Ferrofluids: Studied Through Anisotropic Light Scattering, Corneliu Rablau, Prem Vaishnava, Sudakar Chandran, Ronald Tackett, Gavin Lawes, Ratna Naik
Physics Publications
We have investigated the aggregation and dissociation dynamics of 6-nm size Fe3O4 nanoparticles coated by tetra methyl ammonium hydroxide (TMAH) and the same size γ-Fe2O3 nanoparticles precipitated inside an alginate hydrogel matrix, both in aqueous suspensions, using dc magnetic-field-induced time-dependent light scattering patterns. For the Fe3O4 ferrofluid, a strong anisotropy in light scattering was observed for light propagating perpendicular to the magnetic field. This behavior is attributed to the aggregation of the nanoparticles into chain-like and column-like structures oriented parallel to the magnetic field. A significantly different behavior is observed for the aqueous suspension of γ-Fe2O3 nanoparticles precipitated in alginate …
Electroluminescence Efficiency Enhancement Using Metal Nanoparticles, Jacob B. Khurgin, Greg Sun, R. A. Soref
Electroluminescence Efficiency Enhancement Using Metal Nanoparticles, Jacob B. Khurgin, Greg Sun, R. A. Soref
Physics Faculty Publications
We apply the “effective mode volume” theory to evaluate enhancement of the electroluminescence efficiency of semiconductor emitters placed in the vicinity of isolated metal nanoparticles and their arrays. Using the example of an InGaN/GaN quantum-well active region positioned in close proximity to Ag nanospheres, we show that while the enhancement due to isolated metal nanoparticles is large, only modest enhancement can be obtained with ordered array of those particles. We further conclude that random assembly of isolated particles holds an advantage over the ordered arrays for light emitting devices of finite area.