Regensburg 2022 – wissenschaftliches Programm
KFM 26.7: Vortrag
Donnerstag, 8. September 2022, 18:00–18:15, H10
First magnetic field measurements of a topological insulator based Transmon Qubit — •Anne Schmidt1, Tobias W. Schmitt1, Chenlu Liu2, Albert Hertel1, Christian Dickel3, Michael Schleenvoigt1, Malcolm R. Connolly2,4, Yoichi Ando3, Detlev Grützmacher1, and Peter Schüffelgen1 — 1Peter Grünberg Institute & Jülich-Aachen Research Alliance, Forschungszentrum Jülich — 2Blackett Laboratory, Imperial College London — 3Institute of Physics II, University of Cologne — 4London Centre for Nanotechnology, University College London
Hybrid topological insulator (TI) – superconductor (S) heterostructures are a promising platform for the realization of topologically protected quantum computation based on Majorana zero modes. This promises fewer physical qubits for creating a logical qubit compared to conventional superconducting qubits. Our full in situ device fabrication, which combines selective area growth of thin (Bi,Sb)2Te3 films and stencil deposition of superconductive Nb has already shown to create highly transparent S-TI interfaces. Recently, we have demonstrated that this fabrication process can readily be integrated into cQED structures as building block for a transmon qubit and performed coherence measurements at zero magnetic field. Here, we will expand these measurements to finite magnetic fields, as in-plane magnetic fields are a requirement for restoring the topological phase in confined (Bi,Sb)2Te3 nanostructures. We present initial results on the magnetic field dependence of the T1 lifetime and the qubit’s anharmonicity.