Abstract
| Original language | English |
|---|---|
| Article number | 1353506 |
| Journal | Physica C: Superconductivity and its applications |
| Volume | 565 |
| ISSN | 0921-4534 |
| DOIs | |
| Publication status | Published - 2019 |
Keywords
- MgB2
- Doping
- Carbon
- Methylene blue
- Dye
Cite this
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Increase of the critical current density of MgB2 superconducting bulk samples by means of methylene blue dye additions. / Grivel, Jean-Claude; Rubešová, K.
In: Physica C: Superconductivity and its applications, Vol. 565, 1353506, 2019.Research output: Contribution to journal › Journal article › Research › peer-review
TY - JOUR
T1 - Increase of the critical current density of MgB2 superconducting bulk samples by means of methylene blue dye additions
AU - Grivel, Jean-Claude
AU - Rubešová, K.
PY - 2019
Y1 - 2019
N2 - MgB2 bulk samples were made by means of reaction of elemental Mg and B powders with or without additions of methylene blue trihydrate, a carbon source, which melts at high temperature upon decomposition. The Tc of the MgB2 phase as well as its a-axis parameter were decreased as a result of carbon doping, whereas the c-axis parameter only shows a weak tendency for increasing. The critical current density of MgB2 was improved both in self-field and under applied magnetic field for T ≤ 25 K, the best results being obtained for 0.5–1.0 wt.% methylene blue trihydrate addition. Based on normalized flux pinning force (f(b)) versus reduced field (b) plots, it was found that the flux pinning mechanism at low reduced field is similar for all samples, with a behavior close to the predictions of the point pinning model. However, for b larger than 1, the behavior of f(b) is significantly altered in the methylene blue trihydrate added samples and tends towards the surface pinning model. Methylene blue trihydrate is an efficient carbon source and furthermore provides a liquid phase between 200 °C and 450 °C, which may have some influence on the critical current density improvements at low field.
AB - MgB2 bulk samples were made by means of reaction of elemental Mg and B powders with or without additions of methylene blue trihydrate, a carbon source, which melts at high temperature upon decomposition. The Tc of the MgB2 phase as well as its a-axis parameter were decreased as a result of carbon doping, whereas the c-axis parameter only shows a weak tendency for increasing. The critical current density of MgB2 was improved both in self-field and under applied magnetic field for T ≤ 25 K, the best results being obtained for 0.5–1.0 wt.% methylene blue trihydrate addition. Based on normalized flux pinning force (f(b)) versus reduced field (b) plots, it was found that the flux pinning mechanism at low reduced field is similar for all samples, with a behavior close to the predictions of the point pinning model. However, for b larger than 1, the behavior of f(b) is significantly altered in the methylene blue trihydrate added samples and tends towards the surface pinning model. Methylene blue trihydrate is an efficient carbon source and furthermore provides a liquid phase between 200 °C and 450 °C, which may have some influence on the critical current density improvements at low field.
KW - MgB2
KW - Doping
KW - Carbon
KW - Methylene blue
KW - Dye
U2 - 10.1016/j.physc.2019.1353506
DO - 10.1016/j.physc.2019.1353506
M3 - Journal article
VL - 565
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
M1 - 1353506
ER -