Thin films and nanostructures

Prof. Dr. Michael Huth

Goethe University, Frankfurt am Main

Unconventional superconductivity

Superconducting transition of Co and Cu nanowire
In contact with a W-Ga-C-O superconducting electrode the resistance of a ferromagnetic Co nanowire drops down below 5 K (Tc of W-Ga-C-O). This drop remains visible in large magnetic fields, whereas in a Cu nanowire proximity-induced superconductivity is already destroyed at much lower fields.

A superconducting state in which charge carriers (Cooper pairs) are paired in the odd-frequency spin-triplet state offers promising possibilities for spin-polarized transport in which dissipation is minimized, i.e. to superconducting spintronics which is aimed at understanding and exploiting the interactions arising when superconducting and magnetic order coexist.

When a superconductor is in contact with a ferromagnet, the latter can become superconducting over a length of up to several micrometers. Thus, stimulating a long-ranged superconducting proximity effect by a suitable choice of magnetic nanostructures allows us to study vortex matter in the regime of proximity-induced superconductivity and to advance the development of prototype devices operating with spin-polarized dissipation-free currents.