Dynamic self-assembled structures of nanoparticles can be produced using predominantly electrostatic interactions. Such assemblies were made from large, positively charged Au metal nanoparticles surrounded by an electrostatically bound cloud of smaller, negatively charged CdSe/ZnS or CdTe quantum dots. At low concentrations they are topologically similar to double electric layers of ions and corona-like assemblies linked by polymer chains. They can also be compared to the topological arrangement of some planetary systems in space. The great advantages of the cloud assemblies are (1) their highly dynamic nature compared to more rigid covalently bound assemblies, (2) simplicity of preparation, and (3) exceptional versatility in components and resulting optical properties. Photoluminescence intensity enhancement originating from quantum resonance between excitons and plasmons was observed for CdSe/ZnS quantum dots, although CdTe dots displayed emission quenching. To evaluate more attentively their dynamic behavior, emission data were collected for the cloud-assemblies with different ratios of the components and ionic strengths of the media. The emission of the system passes through a maximum for 80 QDs ∶ 1 Au NP as determined by the structure of the assemblies and light absorption conditions. Ionic strength dependence of luminescence intensity contradicts the predictions based on the Gouy-Chapman theory and osmotic pressure at high ionic strengths due to formation of larger chaotic colloidally stable assemblies. "Cloud" assemblies made from different nanoscale components can be used both for elucidation of most fundamental aspects of nanoparticle interactions, as well as for practical purposes in sensing and biology.
We present a first observational investigation
Of these anomalies across a range of conditions and transitions by carrying out
A survey of low-mass starless cores (in Taurus & Ophiuchus) and high-mass
Protostellar objects (in the G333 giant molecular cloud) using hydrogen cyanide
(HCN) J=1-0 and J=3...
We present a new method for solving the hidden polynomial graph problem
(HPGP) which is a special case of the hidden polynomial problem (HPP). The new
Approach yields an efficient quantum algorithm for the bivariate HPGP even when
The input consists of several level set superpositions, a more diffic...
We investigate both analytically and numerically violations of a Leggett-Garg
Inequality (LGI) for a composite quantum system in contact with two separate
Reservoirs at different temperatures. Remarkably we find that LGI violations
Can be enhanced when a heat current is established at low temperatur...
Pubget Updates sends you emails when Pubget finds new papers that match your search. Use Pubget Updates to get the latest articles for your specialty, written by a colleague, or published by your favorite journals.