Doping effect of nano-Ho{sub 2}O{sub 3} and naphthalene in MgB{sub 2} superconductor prepared by powder-in-sealed-tube method

Journal Article · Sat Mar 21 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4915348· OSTI ID:22399303

Hansdah, J. S.

The effect on crystal structure, critical temperature (T{sub C}), and critical current density (J{sub C}) of bulk MgB{sub 2} doped with nano-Ho{sub 2}O{sub 3} and naphthalene was studied. Among all the samples studied, the sample doped with 2.5 wt. % nano-Ho{sub 2}O{sub 3} have shown the best field dependent critical current density [J{sub C}(H)], i.e., 0.77 × 10{sup 5 }A/cm{sup 2} at 2 T and 10 K. While naphthalene doped MgB{sub 2} sample has shown the least J{sub C}(H) characteristics. The improved J{sub C}(H) characteristics in the nano-Ho{sub 2}O{sub 3} doped MgB{sub 2} samples are attributed to improved flux pinning properties due to the formation of HoB{sub 4} and in naphthalene doped MgB{sub 2} samples. The slight lower T{sub C} value (37.01 K) in naphthalene doped samples is attributed to the occurrence of lattice defect by the substitution of carbon at boron site of MgB{sub 2} superconductor. Lower ΔT{sub C} value implies the lesser anisotropy in all the synthesized samples. The flux pinning force density (F{sub P}/F{sub Pmax}) curves are theoretically analyzed using Dew-Hughes model. The result revealed that point pinning is the dominant pinning mechanism for nano-Ho{sub 2}O{sub 3} doped MgB{sub 2} samples, while, surface and grain boundary pinning become dominant with increasing naphthalene addition in nano-Ho{sub 2}O{sub 3} doped MgB{sub 2} samples.

• OSTI ID: 22399303
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
BORON
CARBON
CRITICAL CURRENT
CRITICAL TEMPERATURE
CRYSTAL DEFECTS
CURRENT DENSITY
DOPED MATERIALS
GRAIN BOUNDARIES
HOLMIUM BORIDES
HOLMIUM OXIDES
MAGNESIUM BORIDES
MAGNETIC FLUX
NANOSTRUCTURES
NAPHTHALENE
POWDERS
SUPERCONDUCTORS