| Autor: |
Sharma, P. U., Raval, P. Y., Mange, P. L., Jani, K. K., Joshi, N. P., Pansara, P. R., Saija, K. G., Meshiya, U. M., Zankat, K. B., Modi, K. B. |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings; 2020, Vol. 2220 Issue 1, p020135-1-020135-4, 4p, 1 Chart, 1 Graph |
| Abstrakt: |
A polycrystalline sample of yttrium iron garnet (Y3Fe5O12) was synthesized by two-steps solid state reaction route and then high energy ball-milled for several hours (3 h, 6 h and 12 h). Temperature (T=300 – 673 K) dependence of dc conductivity (σdc) measurements have been carried out. The presence of two phases, Y3Fe5O12 and yttrium orho-ferrite (YFeO3), as determined from X-ray diffraction patterns analysis in milled samples is also reflected in the variation of σdc as a function of temperature. The milled samples exhibit three distinct regions and two breaks in the temperature range studied. The high transition temperature is nearly equal to the Neel temperature deduced from low field a susceptibility measurements while low transition temperature near to 415 K confirms the presence of yttrium ortho-ferrite phase in all the milled samples. The thermal variation of dc conductivity for all milled specimens are lower than the un-milled sample throughout the temperature range due to the particle size effect, increase in grain boundary volume and the associated impedance to the flow of charge carriers. The activation energies have been calculated and discussed for the different regions. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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