Enhancement of proximity induced superconductivity in planar Germanium

preprint Enhancement of proximity induced superconductivity in planar Germanium draft Kushagra Aggarwal author b22ab905-3539-11eb-84c3-fc159dcd79cb0000-0001-9985-9293 Andrea C Hofmann author 340F461A-F248-11E8-B48F-1D18A9856A87 Daniel Jirovec author 4C473F58-F248-11E8-B48F-1D18A9856A870000-0002-7197-4801 Ivan Prieto Gonzalez author 2A307FE2-F248-11E8-B48F-1D18A9856A870000-0002-7370-5357 Amir Sammak author Marc Botifoll author Sara Marti-Sanchez author Menno Veldhorst author Jordi Arbiol author Giordano Scappucci author Georgios Katsaros author 38DB5788-F248-11E8-B48F-1D18A9856A870000-0001-8342-202X GeKa department Hybrid Semiconductor - Superconductor Quantum Devices project Majorana bound states in Ge/SiGe heterostructures project TOPOLOGICALLY PROTECTED AND SCALABLE QUANTUM BITS project Holes in planar Ge have high mobilities, strong spin-orbit interaction and electrically tunable g-factors, and are therefore emerging as a promising candidate for hybrid superconductorsemiconductor devices. This is further motivated by the observation of supercurrent transport in planar Ge Josephson Field effect transistors (JoFETs). A key challenge towards hybrid germanium quantum technology is the design of high quality interfaces and superconducting contacts that are robust against magnetic fields. By combining the assets of Al, which has a long superconducting coherence, and Nb, which has a significant superconducting gap, we form low-disordered JoFETs with large ICRN products that are capable of withstanding high magnetic fields. We furthermore demonstrate the ability of phase-biasing individual JoFETs opening up an avenue to explore topological superconductivity in planar Ge. The persistence of superconductivity in the reported hybrid devices beyond 1.8 T paves the way towards integrating spin qubits and proximity-induced superconductivity on the same chip. https://research-explorer.ista.ac.at/download/8831/8832/Superconducting_2D_Ge.pdf application/pdfno 2020 eng arXiv 2012.0032210.48550/arXiv.2012.00322 https://research-explorer.ista.ac.at/record/10559 https://research-explorer.ista.ac.at/record/8834 https://research-explorer.ista.ac.at/record/10058 Aggarwal, Kushagra, et al. “Enhancement of Proximity Induced Superconductivity in Planar Germanium.” ArXiv, 2012.00322, doi:<a href="https://doi.org/10.48550/arXiv.2012.00322">10.48550/arXiv.2012.00322</a>. Aggarwal K, Hofmann AC, Jirovec D, et al. Enhancement of proximity induced superconductivity in planar Germanium. arXiv. doi:<a href="https://doi.org/10.48550/arXiv.2012.00322">10.48550/arXiv.2012.00322</a> K. Aggarwal et al., “Enhancement of proximity induced superconductivity in planar Germanium,” arXiv. . Aggarwal, Kushagra, Andrea C Hofmann, Daniel Jirovec, Ivan Prieto Gonzalez, Amir Sammak, Marc Botifoll, Sara Marti-Sanchez, et al. “Enhancement of Proximity Induced Superconductivity in Planar Germanium.” ArXiv, n.d. <a href="https://doi.org/10.48550/arXiv.2012.00322">https://doi.org/10.48550/arXiv.2012.00322</a>. Aggarwal K, Hofmann AC, Jirovec D, Prieto Gonzalez I, Sammak A, Botifoll M, Marti-Sanchez S, Veldhorst M, Arbiol J, Scappucci G, Katsaros G. Enhancement of proximity induced superconductivity in planar Germanium. arXiv, 2012.00322. Aggarwal, K., Hofmann, A. C., Jirovec, D., Prieto Gonzalez, I., Sammak, A., Botifoll, M., … Katsaros, G. (n.d.). Enhancement of proximity induced superconductivity in planar Germanium. arXiv. <a href="https://doi.org/10.48550/arXiv.2012.00322">https://doi.org/10.48550/arXiv.2012.00322</a> K. Aggarwal, A.C. Hofmann, D. Jirovec, I. Prieto Gonzalez, A. Sammak, M. Botifoll, S. Marti-Sanchez, M. Veldhorst, J. Arbiol, G. Scappucci, G. Katsaros, ArXiv (n.d.). 88312020-12-02T10:42:53Z2026-03-08T23:30:18Z