We measure the charge periodicity of Coulomb blockade conductance oscillations of a hybrid InSb-Al island as a function of gate voltage and parallel magnetic field. The periodicity changes from 2e to 1e at a gate-dependent value of the magnetic field, B∗, decreasing from a high to a low limit upon increasing the gate voltage. In the gate voltage region between the two limits, which our numerical simulations indicate to be the most promising for locating Majorana zero modes, we observe correlated oscillations of peak spacings and heights. For positive gate voltages, the 2e-1e transition with low B∗ is due to the presence of non-topological states whose energy quickly disperses below the charging energy due to the orbital effect of the magnetic field. Our measurements demonstrate the importance of a careful exploration of the entire available phase space of a proximitized nanowire as a prerequisite to define future topological qubits.
@article{arxiv.2012.10118,
title = {Full parity phase diagram of a proximitized nanowire island},
author = {J. Shen and G. W. Winkler and F. Borsoi and S. Heedt and V. Levajac and J. Y. Wang and D. van Driel and D. Bouman and S. Gazibegovic and R. L. M. Op Het Veld and D. Car and J. A. Logan and M. Pendharkar and C. J. Palmstrom and E. P. A. M. Bakkers and L. P. Kouwenhoven and B. van Heck},
journal= {arXiv preprint arXiv:2012.10118},
year = {2021}
}
Comments
5 pages, 4 figures plus supplementary. v2: improved manuscript. v3: published version. Raw data and source code available at https://doi.org/10.4121/13333451.v4