Abstract
An amorphous carbon (a-C) powder obtained by decomposition of sucrose was mixed with sulfur and synthesized at 400 °C. Magnetic measurements reveal that the products obtained are inhomogeneous. Some parts show traces of superconductivity at TC = 17 and 42 K. Other parts show unusual magnetic features. (i) Pronounced irreversible peaks around 50 K appear in the first zero-fieldcooled (ZFC) sweep only. (ii) Unexpectedly, these peaks are totally suppressed in the second ZFC runs performed a few minutes later. Around the peak position, the field-cooled (FC) curves cross the ZFC plots, such that ZFC > FC. The two peculiar magnetic observations are connected to each other and are also ascribed to the a-C powder taken from commercial sources. The possibility that impurities cause these magnetic phenomena is excluded.
Original language | English |
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Pages (from-to) | 2547-2555 |
Number of pages | 9 |
Journal | Journal of Superconductivity and Novel Magnetism |
Volume | 25 |
Issue number | 8 |
DOIs | |
State | Published - Dec 2012 |
Keywords
- Amorphous carbon
- Magnetism
- Superconductivity