Reentrant Behavior of Topological Properties in Realistic Planar Josephson Junctions

We investigate the topological properties of realistic planar Josephson junctions (JJ), recently emerged as versatile platforms for topological superconductivity [1,2], as material parameters, external fields, disorder amount and system geometry are varied. We find a much richer and nonuniversal behavior compared to a standard model of topological planar JJs [1, 3]. We also consider the effect of disorder on the presence and measurability of the topological properties of planar JJs embedded in microwave circuit-QED devices [4, 5]. We find that signatures of Majorana bound states persist in the presence of disorder. We show that these systems demonstrate reentrant topological properties under increasing disorder [6]. Our findings not only demonstrate that some disorder may be beneficial to establishing topological phases, but also provide an important step towards experimental detection of non-Abelian statistics and implementing scalable topological quantum computing.

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[6] B. Pekerten, D.M. Monroe, D.S. Brandão, T. Zhou, J.E. Han, I. Žutić, in prep.