Basic and Pinning-Relevant Properties of Superconductors

Superconductors are investigated by different experimental techniques both with respect to fundamental research and future applications. The current research of superconductors is focused on the

• study of superconductivity and magnetism in rare-earth nickel borocarbides RNi₂B₂C (R = Y,Lu,Ho,Tm) and other magnetic superconductors
• investigation of basic superconducting properties as upper critical field, electron-phonon coupling constant and superconducting energy gap in RNi₂B₂C, MgCNi₃ and MgB₂
• vortex matter phase diagram and its anisotropy in MgB₂ and in melt-textured YBCO
• improvement of flux pinning in bulk MgB₂ and in melt-textured YBCO
• development of YBCO trapped field magnets and their application

The superconductors are investigated by magnetization, specific heat, electrical resistance and, in collaboration with our partners from the Institute for Low Temperature Physics and Engineering Kharkov (Ukraine), by point-contact measurements.

recent publications:

A. Waelte, S.-L. Drechsler, G. Fuchs, K.-H. Mueller, K. Nenkov, D. Hinz, L. Schultz, Weak interband coupling in Mg¹⁰B₂: A specific-heat analysis, Phys. Rev. B 73 (2006) 64501/1-7

L. Shlyk, G. Krabbes, G. Fuchs, C. Mickel, B. Rellinghaus, K. Nenkov, Engineering periodic arrays of nanoscale twin boundaries in bulk YBa₂Cu₃O₇ with RuO₂ additions, Appl. Phys. Lett. 88 (2006) 62509/1-3

L. Shlyk, K. Nenkov, G. Krabbes, G. Fuchs, C. Mickel, B. Rellinghaus, Bose-glass signatures in bulk YBa₂Cu₃O_7-x with periodic array of nanoscale twin boundaries, Supercond. Sci. Techn. 19 (2006) 472

C. Krutzler, R. Fuger, M. Eisterer, G. Fuchs, G. Behr, H.W. Weber, Irreversible properties of superconducting HoNi₂B₂C single crystals, Phys.  Rev. B 72 (2005) 144508/1-7

A. Waelte, G. Fuchs, K.-H. Mueller, S.-L. Drechsler, K. Nenkov, L. Schultz, Role of carbon for superconductivity in MgCxNi₃ from specific heat, Phys. Rev. B 72 (2005) 100503(R)/1-4

G. Krabbes, G. Fuchs, W.-R. Canders, H. May, R. Palka, High temperature superconductor bulk materials, Weinheim: Wiley-VCH, 2006, 299 pages