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arXiv · 1401.2671

Topological Superconducting Phases of Weakly Coupled Quantum Wires

Inbar Seroussi·Erez Berg·Yuval Oreg
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Abstract

An array of quantum wires is a natural starting point in realizing two-dimensional topological phases. We study a system of weakly coupled quantum wires with Rashba spin-orbit coupling, proximity coupled to a conventional s-wave superconductor. A variety of topological phases are found in this model. These phases are characterized by "Strong" and "Weak" topological invariants, that capture the appearance of mid-gap Majorana modes (either chiral or non-chiral) on edges along and perpendicular to the wires. In particular, a phase with a single chiral Majorana edge mode (analogous to a $p+ip$ superconductor) can be realized. At special values of the magnetic field and chemical potential, this edge mode is almost completely localized at the outmost wires. In addition, a phase with two co-propagating chiral edge modes is observed. We also consider ways to distinguish experimentally between the different phases in tunneling experiments.

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Inbar Seroussi, Erez Berg, Yuval Oreg. 2014-01-12. Topological Superconducting Phases of Weakly Coupled Quantum Wires. https://doi.org/10.1103/physrevb.89.104523

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