Topological Superconductivity in a Phase-Controlled Josephson Junction
ORAL
Abstract
While signatures of Majorana bound states have been observed in one-dimensional systems, there is an ongoing effort to find alternative platforms that do not require fine-tuning and can be easily scalable. Using a Josephson junction made of HgTe quantum well coupled to thin-film aluminum, we can tune between a trivial and a topological superconducting state by controlling the phase difference φ and an applied in-plane magnetic field, as we measure the tunneling conductance at the edge of the junction. At low magnetic fields, we observe a minimum in the tunneling spectra near zero bias, consistent with a trivial superconductor. As the field increases, the tunneling conductance develops a zero-bias peak which persists over a range of φ that expands systematically with increasing magnetic fields. Consistent with theoretical predictions for this system, our observation establishes this system as a promising platform for realizing topological superconductivity and for creating and manipulating Majorana modes in two-dimensional systems.
*NSF: DMR-1708688, STC CIQM DMR-1231319, GRFP DGE1144152.
Army Research Office: W911NF-18-1-0316. DoD NDSEG.
German Research Foundation, EU ERC-AG program, the Bavarian Ministry of Education, and the Elitenetzwerk Bayern program “Topologische Isolatoren”.
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Presenters
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Hechen Ren
- Watson Laboratory of Applied Physics, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, USA
- Harvard University
- Watson Laboratory of Applied Physics, California Institute of Technology
- Caltech
- Physics, California Institute of Technology