Vortex pinning by magnetic order in ErNi2B2C - art. no. 060501

We have used a miniature linear Hall probe array to make local magnetizatio n measurements of the magnetic superconductor ErNi2B2C (Tc similar or equal to 10.8 K). We show the sharp onset of significant pinning effects in ErNi 2B2C is coincident with the onset of an a-axis incommensurate ordering of t he Er moments at T-a(m) similar or equal to 6 K, below T-c. The data presen ted provide further evidence that certain components of the magnetic order in (R)Ni2B2C materials interact with the vortex lattice and have a profound influence on the nonequilibrium (vortex pinning) properties of the superco nducting state.