Superconducting anisotropy and evidence for intrinsic pinning in single crystalline MgB${}_2$

Abstract

We examine the superconducting anisotropy ${\gamma }_c=(m_c/m_{ab}{)}^{1/2}$ of a metallic high-$T_c$ superconductor MgB${}_2$ by measuring the magnetic torque of a single crystal. The anisotropy ${\gamma }_c$ does not depend sensitively on the applied magnetic field at 10 K. We obtain the anisotropy parameter ${\gamma }_c=4.31\pm 0.14$. The torque curve shows the sharp hysteresis peak when the field is applied parallel to the boron layers. This comes from the intrinsic pinning and is experimental evidence for the occurrence of superconductivity in the boron layers.

REVTeX 4, To be published in Physical Review B

References in corpus (7)

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• Temperature and field dependence of the anisotropy of MgB2
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• Thermally-activated current transport in MgB_2 films
• Anisotropy and internal field distribution of MgB2 in the mixed state at low temperatures
• Anisotropy of the superconducting state properties and phase diagram of MgB2 by torque magnetometry on single crystals
• Penetration depth anisotropy in two-band superconductors
• muSR study of carbon-doped MgB2 superconductors
• Angular Dependent Torque Measurements on CeCoIn${}_5$ Single Crystals
• Coherence lengths and anisotropy in MgB2 superconductor
• Vortex lock-in transition and evidence for transitions among commensurate kinked vortex configurations in single-layered Fe arsenides
• Comment on "Superconducting anisotropy and evidence for intrinsic pinning in single crystalline MgB2"