Mitigation of RF-Induced Critical Current Shifts in NbN Superconducting Nanowire Single-Photon Detectors for Trapped-Ion Readout

Physical Review Applied - APS Journals. 2026. Vol. 25. No. 4. Article 044091.

Suleimen Y., An P. P., Sedykh K., Podlesnyy A., Zarutskiy S. Y., M. Makhlouf

The integration of superconducting nanowire single-photon detectors (SNSPDs) for state readout in trapped-ion quantum processors is hindered by their sensitivity to electromagnetic interference from ion-trapping radio-frequency (RF) fields. We demonstrate a comprehensive mitigation strategy for niobium nitride (NbN) SNSPDs that combines a conducting, optically transparent tin-doped indium oxide (ITO) shield with a nanowire of optimized geometry. Our results show that a 300-nmwide nanowire exhibits greater resilience to RF fields compared to a 100-nm-wide device, sustaining a higher relative critical current at increased RF amplitudes. We also implement a phase-coherent active RF cancelation technique that recovers 92% of the detector’s unperturbed critical current under a 2π×25 MHz RF field. Based on these findings, we demonstrate the possibility of engineering SNSPDs for compatibility with the RF environments of surface electrode traps. This combined approach provides a robust strategy for integrating SNSPDs into trapped-ion systems, which is a critical step towards scalable quantum information processing.

Keywords: SNSPD, niobium nitride (NbN), ion-trapping radio-frequency (RF)