Zusammenfassung
We report the magnetic and superconducting properties of locally
non-centrosymmetric SrPtAs obtained by muon-spin-rotation/relaxation (muSR)
measurements. Zero-field muSR reveals the occurrence of spontaneous static
magnetic fields below the superconducting transition temperature. This finding
implies that the superconducting state of SrPtAs breaks time-reversal symmetry.
The superfluid density as determined by transverse field muSR is exponentially
flat approaching T=0K proving the absence of extended nodes in the gap
function. These experimental results enable us to identify the complex d+id
(chiral d-wave) order parameter as the most probable pairing state in SrPtAs
allowed by symmetry.
Nutzer