Boosting Transparency in Topological Josephson Junctions via Stencil Lithography

Peter Schüffelgen; Daniel Rosenbach; Chuan Li; Tobias Schmitt; Michael Schleenvoigt; Abdur R. Jalil; Jonas Kölzer; Meng Wang; Benjamin Bennemann; Umut Parlak; Lidia Kibkalo; Martina Luysberg; Gregor Mussler; Alexander. A. Golubov; Alexander Brinkman; Thomas Schäpers; Detlev Grützmacher

arXiv · 1711.01665

Boosting Transparency in Topological Josephson Junctions via Stencil Lithography

Peter Schüffelgen·Daniel Rosenbach·Chuan Li·Tobias Schmitt·Michael Schleenvoigt·Abdur R. Jalil·Jonas Kölzer·Meng Wang·Benjamin Bennemann·Umut Parlak·Lidia Kibkalo·Martina Luysberg·Gregor Mussler·Alexander. A. Golubov·Alexander Brinkman·Thomas Schäpers·Detlev Grützmacher

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Abstract

Hybrid devices comprised of topological insulator (TI) nanostructures in proximity to s-wave superconductors (SC) are expected to pave the way towards topological quantum computation. Fabrication under ultra-high vacuum conditions is necessary to attain high quality of TI-SC hybrid devices, because the physical surfaces of V-VI three-dimensional TIs suffer from degradation at ambient conditions. Here, we present an in-situ process, which allows to fabricate such hybrids by combining molecular beam epitaxy and stencil lithography. As-prepared Josephson junctions show nearly perfect interface transparency and very large $I_CR_N$ products. The Shapiro response of radio frequency measurements indicates the presence of gapless Andreev bound states, so-called Majorana bound states.

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Peter Schüffelgen, Daniel Rosenbach, Chuan Li, Tobias Schmitt, Michael Schleenvoigt, Abdur R. Jalil, Jonas Kölzer, Meng Wang, Benjamin Bennemann, Umut Parlak, Lidia Kibkalo, Martina Luysberg, Gregor Mussler, Alexander. A. Golubov, Alexander Brinkman, Thomas Schäpers, Detlev Grützmacher. 2017-11-05. Boosting Transparency in Topological Josephson Junctions via Stencil Lithography. https://arxiv.org/abs/1711.01665

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