Device splits and recombines superconducting electron pairs  December 27, 2019 Cooper pair splitting (CPS) can induce nonlocal correlation between two normal conductors that are coupled to a superconductor. An international team of researchers (Japan, China, Sweden) investigated CPS by using a Josephson junction of a gate-tunable ballistic InAs double nanowire. The measured switching current in the two nanowires was significantly larger than the sum of the switching current into the respective nanowires, indicating that interwire superconductivity is dominant compared with intrawire superconductivity. From its dependence on the number of propagating channels in the nanowires, the observed CPS was assigned to one-dimensional electron-electron interaction. The results will […]

Computing faster with quasi-particles

Eurekalert  May 10, 2019 Majorana particles can emerge as quasi-particles in topological superconductors and represent ideal building blocks for topological quantum computers. Whereas previous experiments in this field have mostly focused on one-dimensional systems an international team of researchers (USA – Harvard University, Caltech, IBM Watson Research Laboratory, Germany) succeeded in going to two-dimensional systems. They observed a topological phase transition in their proof of concept system which implies the appearance of Majorana fermions in phase-controlled Josephson junctions confirming the advantages of two-dimensional system compared to previous one-dimensional platforms. An improved control of Majorana fermions represents an important step towards […]