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arXiv · 1911.03802

Signature of a pair of Majorana zero modes in superconducting gold surface states

Sujit Manna·Peng Wei·Yingming Xie·Kam Tuen Law·Patrick Lee·Jagadeesh Moodera
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Abstract

Under certain conditions, a fermion in a superconductor can separate in space into two parts known as Majorana zero modes, which are immune to decoherence from local noise sources and are attractive building blocks for quantum computers. Promising experimental progress has been made to demonstrate Majorana zero modes in materials with strong spin-orbit coupling proximity coupled to superconductors. Here we report signatures of Majorana zero modes in a new material platform utilizing the surface states of gold. Using scanning tunneling microscope to probe EuS islands grown on top of gold nanowires, we observe two well separated zero bias tunneling conductance peaks aligned along the direction of the applied magnetic field, as expected for a pair of Majorana zero modes. This platform has the advantage of having a robust energy scale and the possibility of realizing complex designs using lithographic methods.

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Sujit Manna, Peng Wei, Yingming Xie, Kam Tuen Law, Patrick Lee, Jagadeesh Moodera. 2019-11-09. Signature of a pair of Majorana zero modes in superconducting gold surface states. https://doi.org/10.1073/pnas.1919753117

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