Ernesto Govea Alcaide | Universidad de Oriente - Cuba
| Grant number: | 09/51562-3 |
| Support type: | Research Grants - Visiting Researcher Grant - International |
| Duration: | September 28, 2009 - November 25, 2009 |
| Field of knowledge: | Physical Sciences and Mathematics - Physics |
| Principal Investigator: | Renato de Figueiredo Jardim |
| Grantee: | Renato de Figueiredo Jardim |
| Visiting researcher: | Ernesto Govea Alcaide |
| Visiting researcher institution: | Universidad de Oriente, Cuba |
| Home Institution: | Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil |
| Associated research grant: | 05/53241-9 - Study of intergranular phenomena in ceramic materials, AP.TEM |
Abstract
In the last research plan we have obtained bi1.64Pb0.64Sr2Ca2Cu3Oy (Bi-2223) samples which, by using the scherer formula, are composed by grains with sizes ranging from 20 nm to 5μm. Preliminary magnetic measurements indicated that: (i) as the size of grains decreases, the superconducting transition begins to branch out and (ii) for temperatures lower than a certain value, Teff, the magnetic susceptibility as a function of temperature shows a paramagnetic-like behavior transport and magnetic properties of the Bi-2223 nanoparticles. We will concentrate efforts for determining the grain size distribution of samples. The main point here is to correlate the above mentioned distribution with the transport and magnetic properties in order to search for crossover from bulk to few-electron limit in small superconducting grains. (AU)