Topological superconductivity in hybrid devices


Topological superconductivity can emerge from the combination of conventional superconductivity in a metal and strong spin–orbit coupling in a semiconductor when they are made into a hybrid device. The most exciting manifestation of topological superconductivity is the Majorana zero modes that are predicted to exist at the ends of the proximatized nanowires. In this Perspective, we review the evidence for the existence of Majorana zero modes that has accumulated in numerous experiments and the remaining uncertainties, and discuss what additional evidence is desirable. One very important factor for future development is the quality of the interface between the superconductor and semiconductor; we sketch out where further progress in the materials science of these interfaces can take us. We then discuss the path towards applying these modes in topologically protected quantum computing and observing more exotic kinds of superconductivity based on the same materials platform, and how to make connections to high-energy physics.

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Fig. 1: The concept of topological superconductivity using a spinless superconductor primer.
Fig. 2: Zero-bias conductance peaks can appear due to MZMs or due to trivial ABSs.
Fig. 3: Materials considerations for superconductor/semiconductor hybrid systems.
Fig. 4: Future exotic topologically superconducting phases.


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We thank S. Das Sarma for comments. S.M.F. is supported by NSF DMR-1906325, NSF PIRE-1743717, ONR and ARO. M.J.M is supported by Microsoft Quantum. J.S. is supported by the NSF-DMR1555135 and helpful discussions at the KITP under Grant no. NSF PHY-1748958.

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Frolov, S.M., Manfra, M.J. & Sau, J.D. Topological superconductivity in hybrid devices. Nat. Phys. 16, 718–724 (2020).

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