Vortex dynamics in superconductors without inversion symmetry

Abstract

In this chapter we give an overview on some recent experimental results on vortex dynamics in the non-centrosymmetric superconductors CePt 3Si and Li 2Pt 3B. In both compounds the flux creep from a metastable vortex configuration is anomalously slow-slower than in any other superconductor. Additionally, Li 2Pt 3B shows very strong avalanche-like flux release after waiting times of several hours at millikelvin temperatures. Since critical currents are also low, the origin of these properties cannot be simply attributed to conventional flux pinning by defects. We speculate that both properties might be connected with crystalline twinning of the samples. We show that twin boundaries in non-centrosymmetric superconductors can host states with broken time reversal symmetry which can carry fractionally quantized flux lines. These flux lines are strongly pinned to the twin boundaries such that they impede the usual flux motion without affecting the critical current. © Springer-Verlag Berlin Heidelberg 2012.