Physics – Condensed Matter – Superconductivity
Scientific paper
2002-10-31
Physica C 385, 143 (2003)
Physics
Condensed Matter
Superconductivity
12 pages, 8 figures, Physica C in print (invited paper for a special issue on MgB2)
Scientific paper
10.1016/S0921-4534(02)02297-9
The angular and temperature dependence of the upper critical field Hc2 in MgB2 was determined from torque magnetometry measurements on single crystals. The Hc2 anisotropy gamma_H was found to decrease with increasing temperature, in disagreement with the anisotropic Ginzburg-Landau theory, which predicts that the gamma_H is temperature independent. This behaviour can be explained by the two band nature of superconductivity in MgB2. An analysis of measurements of the reversible torque in the mixed state yields a field dependent effective anisotropy gamma_eff, which can be at least partially explained by different anisotropies of the penetration depth and the upper critical field. It is shown that a peak effect in fields of about 0.85 Hc2 is a manifestation of an order-disorder phase transition of vortex matter. The H-T phase diagram of MgB2 for H//c correlates with the intermediate strength of thermal fluctuations in MgB2, as compared to those in high and low Tc superconductors.
Angst Manuel
Jun Jinha
Karpinski Janusz
Kazakov Sergey M.
Keller Hugo
No associations
LandOfFree
Anisotropy of the superconducting state properties and phase diagram of MgB2 by torque magnetometry on single crystals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Anisotropy of the superconducting state properties and phase diagram of MgB2 by torque magnetometry on single crystals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anisotropy of the superconducting state properties and phase diagram of MgB2 by torque magnetometry on single crystals will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-577951