Indium Oxide Resistance Fluctuation Measurements

For superconducting indium oxide films with higher disorder, a more conventional superconductor-insulator transition is observed. Low frequency resistance measurements performed on such a film are shown in this dataset. Contrary to initial expectations there were no significant changes in the noise properties near the quantum critical point. However, it was found that the noise varied in a way that was consistent with predictions based on a percolation model. Specifically, the noise properties suggest that the superconductor-insulator transition can be modeled by p-model percolation. This model is based on random Josephson junction array models which have been used extensively to explain the properties of granular superconductors.

Description
Voltage versus time traces for indium oxide film that undergoes an SIT. The noise measurement was in a Wheatstone bridge configuration and measured resistance fluctuations. Resistance versus temperature sweeps are also included. All data was measured in an Oxford Kelvinox K400 dilution refrigerator.

Funding information
Sponsorship: Sponsorship: This work was supported by the National Science Foundation under Grant Nos. DMR-1209578 and DMR-1704456. Portions of this work were conducted in the Minnesota Nano Center, which is supported by the National Science Foundation through the National Nano Coordinated Infrastructure Network (NNCI) under Award Number ECCS-1542202.