Unexpected superconductivity at mesoscopic point-contacts on a Dirac Semimetal

I will first give a brief overview of conventional and unconventional superconductivity and discuss how the subject area of superconductivity has recently received renewed interest following the discovery of several new superconductors showing unexpectedly high critical temperatures and exotic order parameter symmetries. After that, I will present the discovery of a new unconventional superconducting phase at mesoscopic point-contacts formed on the 3-dimensional Dirac semimetal Cd3As2 by simply touching the surface of Cd3As2 with a sharp metallic needle. I will discuss how simple measurements of the current-voltage characteristics of such point-contacts led to this discovery. The I-V characteristics have also shown special features that might be related to topological superconductivity. 

L. Aggarwal, A. Gaurav, G. S. Thakur, Z. Haque, A. K. Ganguli, G. Sheet, arXiv:1410.2072 (to appear in Nature Materials)